get-pick-list.sh: Include commits mentionining "CC: mesa-stable..." in pick list

We recently adopted a new convention that patches can be nominated for the
stable branch by including a line in the commit message as follows:

	CC: mesa-stable@lists.freedesktop.org

This is a convenient syntax as "git send-email" will notice this line and
automatically copy the resulting patch email to the mesa-stable mailing list.

Here we extend the regular expression in the get-pick-list.sh script to also
notice this pattern, (as well as the traditional "NOTE: This patch is a
candidate..." form.

bin/get-pick-list.sh

@@ -14,7 +14,7 @@ git log --reverse --grep="cherry picked from commit" origin/master..HEAD |\
 	sed -e 's/^[[:space:]]*(cherry picked from commit[[:space:]]*//' -e 's/)//' > already_picked
 
 # Grep for commits that were marked as a candidate for the stable tree.
-git log --reverse --pretty=%H -i --grep='^[[:space:]]*NOTE: .*[Cc]andidate' HEAD..origin/master |\
+git log --reverse --pretty=%H -i --grep='^\([[:space:]]*NOTE: .*[Cc]andidate\|CC:[[:space:]]*mesa-stable\)' HEAD..origin/master |\
 while read sha
 do
 	# Check to see whether the patch is on the ignore list.