Fix up some further cases of missing or extraneous spaces in diagnostics

Fix up some further cases of missing or extraneous spaces in diagnostics

Given the recent PR119406 I've tried to grep for concatenated string
literals without space at the end of one line and at the start of next line,
unless it was obviously intentional.
Furthermore, I've then looked through gcc.pot looking for 2 adjacent spaces
and looking back if that wasn't the case of "something "
" with spaces at both sides".

Here is the result from that.

I think just the c.opt change needs an explanation, the "" in the
description is simply eaten up somewhere during the option processing and
gcc -v --help before this patch was displaying
  -Wdeprecated-literal-operator Warn about deprecated space between  and suffix in a user-defined literal operator.

2025-03-22  Jakub Jelinek  <jakub@redhat.com>

gcc/
	* gimplify.cc (warn_switch_unreachable_and_auto_init_r): Add missing
	space in the middle of diagnostics.

(cherry picked from commit 20360e4b6b5a63bc65d1855a7ecf22eb7148a452)