postgresql: properly stop service

postmaster always detaches from procd, work around by using
pg_ctl to stop the server.

Signed-off-by: Daniel Golle <daniel@makrotopia.org>

libs/postgresql/files/postgresql.init

@@ -65,6 +65,12 @@ reload_service() {
 	/usr/bin/pg_ctl reload -U postgres -D "${pgdata}" -s
 }
 
+stop_service() {
+	config_load "postgresql"
+	config_get pgdata config PGDATA
+	/usr/bin/pg_ctl stop -U postgres -D "${pgdata}" -s
+}
+
 status() {
 	config_load "postgresql"
 	config_get pgdata config PGDATA