smb: remove redundant check

->setlease() is never called on non-regular files now. So remove the
check from cifs_setlease().

Link: https://lore.kernel.org/r/170716318935.13976.13465352731929804157@noble.neil.brown.nameSigned-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Christian Brauner <brauner@kernel.org>

fs/smb/client/cifsfs.c

@@ -1094,9 +1094,6 @@ cifs_setlease(struct file *file, int arg, struct file_lease **lease, void **priv
 	struct inode *inode = file_inode(file);
 	struct cifsFileInfo *cfile = file->private_data;
 
-	if (!(S_ISREG(inode->i_mode)))
-		return -EINVAL;
-
 	/* Check if file is oplocked if this is request for new lease */
 	if (arg == F_UNLCK ||
 	    ((arg == F_RDLCK) && CIFS_CACHE_READ(CIFS_I(inode))) ||