libceph: remove unnecessary non NULL check for request_key

request_key never return NULL,so no need do non-NULL check.
Signed-off-by: NYueHaibing <yuehaibing@huawei.com>
Reviewed-by: NIlya Dryomov <idryomov@gmail.com>
Signed-off-by: NIlya Dryomov <idryomov@gmail.com>

net/ceph/ceph_common.c

@@ -304,7 +304,7 @@ static int get_secret(struct ceph_crypto_key *dst, const char *name) {
 	struct ceph_crypto_key *ckey;
 
 	ukey = request_key(&key_type_ceph, name, NULL);
-	if (!ukey || IS_ERR(ukey)) {
+	if (IS_ERR(ukey)) {
 		/* request_key errors don't map nicely to mount(2)
 		   errors; don't even try, but still printk */
 		key_err = PTR_ERR(ukey);