staging: lustre: fix sparse warnings: static function declaration

Signed-off-by: Vincenzo Scotti <vinc94@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/lustre/lustre/ptlrpc/layout.c

@@ -1999,7 +1999,7 @@ static void *__req_capsule_get(struct req_capsule *pill,
 /**
  * Dump a request and/or reply
  */
-void __req_capsule_dump(struct req_capsule *pill, enum req_location loc)
+static void __req_capsule_dump(struct req_capsule *pill, enum req_location loc)
 {
 	const struct    req_format *fmt;
 	const struct    req_msg_field *field;