NFS: start printks w/ NFS: even if __func__ shown

This patch addresses printks that have some context to show that they are
from fs/nfs/, but for the sake of consistency now start with NFS:

Signed-off-by: Weston Andros Adamson <dros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
diff --git a/fs/nfs/idmap.c b/fs/nfs/idmap.c
index 91b1e2a..62264e0 100644
--- a/fs/nfs/idmap.c
+++ b/fs/nfs/idmap.c
@@ -558,11 +558,13 @@
 			 * here.
 			 */
 			if (rpc_rmdir(parent))
-				printk(KERN_ERR "%s: failed to remove clnt dir!\n", __func__);
+				printk(KERN_ERR "NFS: %s: failed to remove "
+					"clnt dir!\n", __func__);
 		}
 		break;
 	default:
-		printk(KERN_ERR "%s: unknown event: %ld\n", __func__, event);
+		printk(KERN_ERR "NFS: %s: unknown event: %ld\n", __func__,
+			event);
 		return -ENOTSUPP;
 	}
 	return err;