Comment 3 for bug 1877968

Just got this bug on fully updated Ubuntu 20.04 LTS, installation failed with:

```
$ sudo apt install gammu-smsd
Reading package lists... Done
Building dependency tree
Reading state information... Done
The following additional packages will be installed:
  libdbi1 libgammu-i18n libgammu8 libgsmsd8 libodbc1 libpq5
Suggested packages:
  gammu gammu-doc libmyodbc odbc-postgresql tdsodbc unixodbc-bin
The following NEW packages will be installed:
  gammu-smsd libdbi1 libgammu-i18n libgammu8 libgsmsd8 libodbc1 libpq5
0 upgraded, 7 newly installed, 0 to remove and 0 not upgraded.
Need to get 1 073 kB of archives.
After this operation, 4 343 kB of additional disk space will be used.
Do you want to continue? [Y/n]
Get:1 http://archive.ubuntu.com/ubuntu focal/universe amd64 libgammu8 amd64 1.41.0-1 [424 kB]
Get:2 http://archive.ubuntu.com/ubuntu focal/main amd64 libdbi1 amd64 0.9.0-5 [27,3 kB]
Get:3 http://archive.ubuntu.com/ubuntu focal/main amd64 libodbc1 amd64 2.3.6-0.1build1 [189 kB]
Get:4 http://archive.ubuntu.com/ubuntu focal-updates/main amd64 libpq5 amd64 12.8-0ubuntu0.20.04.1 [116 kB]
Get:5 http://archive.ubuntu.com/ubuntu focal/universe amd64 libgsmsd8 amd64 1.41.0-1 [45,2 kB]
Get:6 http://archive.ubuntu.com/ubuntu focal/universe amd64 gammu-smsd amd64 1.41.0-1 [66,8 kB]
Get:7 http://archive.ubuntu.com/ubuntu focal/universe amd64 libgammu-i18n all 1.41.0-1 [204 kB]
Fetched 1 073 kB in 2s (608 kB/s)
Selecting previously unselected package libgammu8.
(Reading database ... 252667 files and directories currently installed.)
Preparing to unpack .../0-libgammu8_1.41.0-1_amd64.deb ...
Unpacking libgammu8 (1.41.0-1) ...
Selecting previously unselected package libdbi1:amd64.
Preparing to unpack .../1-libdbi1_0.9.0-5_amd64.deb ...
Unpacking libdbi1:amd64 (0.9.0-5) ...
Selecting previously unselected package libodbc1:amd64.
Preparing to unpack .../2-libodbc1_2.3.6-0.1build1_amd64.deb ...
Unpacking libodbc1:amd64 (2.3.6-0.1build1) ...
Selecting previously unselected package libpq5:amd64.
Preparing to unpack .../3-libpq5_12.8-0ubuntu0.20.04.1_amd64.deb ...
Unpacking libpq5:amd64 (12.8-0ubuntu0.20.04.1) ...
Selecting previously unselected package libgsmsd8.
Preparing to unpack .../4-libgsmsd8_1.41.0-1_amd64.deb ...
Unpacking libgsmsd8 (1.41.0-1) ...
Selecting previously unselected package gammu-smsd.
Preparing to unpack .../5-gammu-smsd_1.41.0-1_amd64.deb ...
Unpacking gammu-smsd (1.41.0-1) ...
Selecting previously unselected package libgammu-i18n.
Preparing to unpack .../6-libgammu-i18n_1.41.0-1_all.deb ...
Unpacking libgammu-i18n (1.41.0-1) ...
Setting up libdbi1:amd64 (0.9.0-5) ...
Setting up libpq5:amd64 (12.8-0ubuntu0.20.04.1) ...
Setting up libgammu8 (1.41.0-1) ...
Setting up libgammu-i18n (1.41.0-1) ...
Setting up libodbc1:amd64 (2.3.6-0.1build1) ...
Setting up libgsmsd8 (1.41.0-1) ...
Setting up gammu-smsd (1.41.0-1) ...
Failed to start gammu-smsd.service: Unit gammu-smsd.service has a bad unit file setting.
See system logs and 'systemctl status gammu-smsd.service' for details.
invoke-rc.d: initscript gammu-smsd, action "start" failed.
● gammu-smsd.service - SMS daemon for Gammu
     Loaded: bad-setting (Reason: Unit gammu-smsd.service has a bad unit file setting.)
     Active: inactive (dead)
       Docs: man:gammu-smsd(1)

окт 31 11:23:49 focal systemd[1]: /lib/systemd/system/gammu-smsd.service:9: Neither a valid executable name nor an absolute path: ${CMAKE_INSTALL_FUL
L_BINDIR}/gammu-smsd
окт 31 11:23:49 focal systemd[1]: gammu-smsd.service: Unit configuration has fatal error, unit will not be started.
окт 31 11:24:59 focal systemd[1]: /lib/systemd/system/gammu-smsd.service:9: Neither a valid executable name nor an absolute path: ${CMAKE_INSTALL_FUL
L_BINDIR}/gammu-smsd
окт 31 11:24:59 focal systemd[1]: gammu-smsd.service: Unit configuration has fatal error, unit will not be started.
окт 31 11:25:00 focal systemd[1]: /lib/systemd/system/gammu-smsd.service:9: Neither a valid executable name nor an absolute path: ${CMAKE_INSTALL_FUL
L_BINDIR}/gammu-smsd
окт 31 11:25:00 focal systemd[1]: gammu-smsd.service: Unit configuration has fatal error, unit will not be started.
окт 31 11:26:50 focal systemd[1]: /lib/systemd/system/gammu-smsd.service:9: Neither a valid executable name nor an absolute path: ${CMAKE_INSTALL_FUL
L_BINDIR}/gammu-smsd
окт 31 11:26:50 focal systemd[1]: gammu-smsd.service: Unit configuration has fatal error, unit will not be started.
окт 31 11:26:50 focal systemd[1]: /lib/systemd/system/gammu-smsd.service:9: Neither a valid executable name nor an absolute path: ${CMAKE_INSTALL_FUL
L_BINDIR}/gammu-smsd
окт 31 11:26:50 focal systemd[1]: gammu-smsd.service: Unit configuration has fatal error, unit will not be started.
dpkg: error processing package gammu-smsd (--configure):
 installed gammu-smsd package post-installation script subprocess returned error exit status 1
Processing triggers for systemd (245.4-4ubuntu3.13) ...
Processing triggers for man-db (2.9.1-1) ...
Processing triggers for libc-bin (2.31-0ubuntu9.2) ...
Errors were encountered while processing:
 gammu-smsd
E: Sub-process /usr/bin/dpkg returned an error code (1)

```