feedback "mount: mount(2) failed: No such file or directory" is unhelpful

[Karl-Philipp Richter]

The feedback `mount: mount(2) failed: No such file or directory` after `sudo mount -a` is obviously very unhelpful as it doesn't provide any information about the reason for the failure nor further instructions.

Please consider improving your integration test and code review routines in order to avoid such issues in the future.

ProblemType: Bug
DistroRelease: Ubuntu 16.04
Package: mount 2.27.1-6ubuntu1
ProcVersionSignature: Ubuntu 4.4.0-9.24-generic 4.4.3
Uname: Linux 4.4.0-9-generic x86_64
NonfreeKernelModules: openafs
ApportVersion: 2.20-0ubuntu3
Architecture: amd64
Date: Mon Mar 14 20:39:29 2016
InstallationDate: Installed on 2015-04-20 (329 days ago)
InstallationMedia: Ubuntu-Server 14.10 "Utopic Unicorn" - Release amd64 (20141022.2)
SourcePackage: util-linux
UpgradeStatus: Upgraded to xenial on 2016-03-03 (10 days ago)