git-merge: Don't use -p when outputting summary

-p is not needed and we only want diffstat and summary.

Signed-off-by: Timo Hirvonen <tihirvon@gmail.com>
Signed-off-by: Junio C Hamano <junkio@cox.net>

git-merge.sh

@@ -55,7 +55,7 @@ finish () {
 
 	case "$no_summary" in
 	'')
-		git-diff-tree -p --stat --summary -M "$head" "$1"
+		git-diff-tree --stat --summary -M "$head" "$1"
 		;;
 	esac
 }