Add process name and pid to locks warning

It's fairly useless to complain about using an obsolete feature without
telling the user which process used it. My Fedora desktop randomly drops
this message, but I would really need this patch to figure out what
triggers is.

[ jlayton: print pid as well as process name ]

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Jeff Layton <jlayton@kernel.org>

fs/locks.c

@@ -2096,7 +2096,7 @@ SYSCALL_DEFINE2(flock, unsigned int, fd, unsigned int, cmd)
 	 * throw a warning to let people know that they don't actually work.
 	 */
 	if (cmd & LOCK_MAND) {
-		pr_warn_once("Attempt to set a LOCK_MAND lock via flock(2). This support has been removed and the request ignored.\n");
+		pr_warn_once("%s(%d): Attempt to set a LOCK_MAND lock via flock(2). This support has been removed and the request ignored.\n", current->comm, current->pid);
 		return 0;
 	}