The bash_completion scriptlet for desktop-file-validate does
not check if the variable "filenames" is unset.  This
results in a warning if running in a shell with "set -u".

One way to replicate the problem is to have "set -u" in
one's ~/.bashrc, then log in through ssh.  There will be an
error message "-bash: filenames: unbound variable"
immediately after the MOTD.

The attached patch fixes the problem.