ceph: do not modify fi->frag in need_reset_readdir()

Commit f3c4ebe ("ceph: using hash value to compose dentry offset")
modified "if (fpos_frag(new_pos) != fi->frag)" to "if (fi->frag |=
fpos_frag(new_pos))" in need_reset_readdir(), thus replacing a
comparison operator with an assignment one.

This looks like a typo which is reported by clang when building the
kernel with some warning flags:

    fs/ceph/dir.c:600:22: error: using the result of an assignment as a
    condition without parentheses [-Werror,-Wparentheses]
            } else if (fi->frag |= fpos_frag(new_pos)) {
                       ~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~
    fs/ceph/dir.c:600:22: note: place parentheses around the assignment
    to silence this warning
            } else if (fi->frag |= fpos_frag(new_pos)) {
                                ^
                       (                             )
    fs/ceph/dir.c:600:22: note: use '!=' to turn this compound
    assignment into an inequality comparison
            } else if (fi->frag |= fpos_frag(new_pos)) {
                                ^~
                                !=

Fixes: f3c4ebe ("ceph: using hash value to compose dentry offset")
Signed-off-by: Nicolas Iooss <nicolas.iooss_linux@m4x.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

fs/ceph/dir.c

@@ -597,7 +597,7 @@ static bool need_reset_readdir(struct ceph_file_info *fi, loff_t new_pos)
 	if (is_hash_order(new_pos)) {
 		/* no need to reset last_name for a forward seek when
 		 * dentries are sotred in hash order */
-	} else if (fi->frag |= fpos_frag(new_pos)) {
+	} else if (fi->frag != fpos_frag(new_pos)) {
 		return true;
 	}
 	rinfo = fi->last_readdir ? &fi->last_readdir->r_reply_info : NULL;