stash: simplify option parser for create

The option parser for create unnecessarily checks "$1" inside a case
statement that matches "$1" in the first place.

Signed-off-by: Ramkumar Ramachandra <artagnon@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

git-stash.sh

@@ -546,10 +546,7 @@ clear)
 	clear_stash "$@"
 	;;
 create)
-	if test $# -gt 0 && test "$1" = create
-	then
-		shift
-	fi
+	shift
 	create_stash "$*" && echo "$w_commit"
 	;;
 drop)