ecryptfs_inode_permission() doesn't need to bail out on RCU

... now that inode_permission() can take MAY_NOT_BLOCK and handle it
properly.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

fs/ecryptfs/inode.c

@@ -944,8 +944,6 @@ int ecryptfs_truncate(struct dentry *dentry, loff_t new_length)
 static int
 ecryptfs_permission(struct inode *inode, int mask)
 {
-	if (mask & MAY_NOT_BLOCK)
-		return -ECHILD;
 	return inode_permission(ecryptfs_inode_to_lower(inode), mask);
 }