bin/get-pick-list.sh: prefix output with "[stable] "

With later commits we'll fold all the different scripts into one.
Add the explicit prefix, so that we know the origin of the nomination

v2:
 - pass the sha as argument to the function
 - swap $tag = none for an else statment (Juan)
 - grep -q instead of using a variable (Eric)
 - print the tag and commit oneline separately (Eric)

v3:
 - drop unused "tag=none" assignment (Juan)
 - typo nomination

Cc: mesa-stable@lists.freedesktop.org
Reviewed-by: Juan A. Suarez <jasuarez@igalia.com>
Reviewed-by: Eric Engestrom <eric.engestrom@intel.com> (v2)
Signed-off-by: Emil Velikov <emil.velikov@collabora.com>

bin/get-pick-list.sh

@@ -7,6 +7,14 @@
 # $ bin/get-pick-list.sh
 # $ bin/get-pick-list.sh > picklist
 # $ bin/get-pick-list.sh | tee picklist
+#
+# The output is as follows:
+# [nomination_type] commit_sha commit summary
+
+is_stable_nomination()
+{
+	git show --summary "$1" | grep -q -i -o "CC:.*mesa-stable"
+}
 
 # Use the last branchpoint as our limit for the search
 latest_branchpoint=`git merge-base origin/master HEAD`
@@ -32,6 +40,13 @@ do
 		continue
 	fi
 
+	if is_stable_nomination "$sha"; then
+		tag=stable
+	else
+		continue
+	fi
+
+	printf "[ %8s ] " "$tag"
 	git --no-pager show --summary --oneline $sha
 done