pointless since...

commit 33761c69
Date:   Sun Dec 3 23:35:26 2017 -0500

    vcl-svp: Store 24-bit images in 3-byte pixels

squashed the effort to percolate preferred target format as bitmap storage
format

Change-Id: I8a5367d4d7d251d5dd37011d0e51ab09cf5c57ac
Reviewed-on: https://gerrit.libreoffice.org/67055
Tested-by: Jenkins
Reviewed-by: Caolán McNamara <caolanm@redhat.com>
Tested-by: Caolán McNamara <caolanm@redhat.com>