Comment 0 for bug 1814575

Fix this:

On some Thinkpads (up to now, no other manufacturers appear to show this), db can be reported to be empty even though it's not. It seems to be a firmware issue, but it's one we can work around.

So, fix this type of failure:

Setting up grub-efi-amd64-signed (1.112+2.02+dfsg1-5ubuntu10) ...
db is empty
Can't open *.der for reading, No such file or directory
140033418155072:error:02001002:system library:fopen:No such file or directory:../crypto/bio/bss_file.c:72:fopen('*.der','rb')
140033418155072:error:2006D080:BIO routines:BIO_new_file:no such file:../crypto/bio/bss_file.c:79:
unable to load certificate
dpkg: error processing package grub-efi-amd64-signed (--configure):
 installed grub-efi-amd64-signed package post-installation script subprocess returned error exit status 1
dpkg: dependency problems prevent processing triggers for shim-signed:
 shim-signed depends on grub-efi-amd64-signed | grub-efi-arm64-signed; however:
  Package grub-efi-amd64-signed is not configured yet.
  Package grub-efi-arm64-signed is not installed.

dpkg: error processing package shim-signed (--configure):
 dependency problems - leaving triggers unprocessed
Errors were encountered while processing:
 grub-efi-amd64-signed
 shim-signed
E: Sub-process /usr/bin/dpkg returned an error code (1)