nfs: use %p[dD] instead of open-coded (and often racy) equivalents

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index d53d678..75e46bb 100644
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -3738,9 +3738,8 @@
 	};
 	int			status;
 
-	dprintk("%s: dentry = %s/%s, cookie = %Lu\n", __func__,
-			dentry->d_parent->d_name.name,
-			dentry->d_name.name,
+	dprintk("%s: dentry = %pd2, cookie = %Lu\n", __func__,
+			dentry,
 			(unsigned long long)cookie);
 	nfs4_setup_readdir(cookie, NFS_I(dir)->cookieverf, dentry, &args);
 	res.pgbase = args.pgbase;