inode->i_op is never NULL

We used to have rather schizophrenic set of checks for NULL ->i_op even
though it had been eliminated years ago.  You'd need to go out of your
way to set it to NULL explicitly _and_ a bunch of code would die on
such inodes anyway.  After killing two remaining places that still
did that bogosity, all that crap can go away.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/fs/cifs/inode.c b/fs/cifs/inode.c
index f247da9..5ab9896 100644
--- a/fs/cifs/inode.c
+++ b/fs/cifs/inode.c
@@ -1641,7 +1641,7 @@
 	i_size_write(inode, offset);
 	spin_unlock(&inode->i_lock);
 out_truncate:
-	if (inode->i_op && inode->i_op->truncate)
+	if (inode->i_op->truncate)
 		inode->i_op->truncate(inode);
 	return 0;
 out_sig: