scripts: fix commit check for empty list

When running check-git-log.sh on a clean tree it was complaining
of a wrong empty headline because '^[^:]*$' was matching.
It is fixed by matching at least one character with +.

Signed-off-by: Thomas Monjalon <thomas.monjalon@6wind.com>

scripts/check-git-log.sh

@@ -63,7 +63,7 @@ bad=$(echo "$headlines" | grep --color=always \
 	-e '\.$' \
 	-e '[,;!?&|]' \
 	-e ':.*_' \
-	-e '^[^:]*$' \
+	-e '^[^:]\+$' \
 	-e ':[^ ]' \
 	-e ' :' \
 	| sed 's,^,\t,')