nvmet: remove duplicate NULL initialization for req->ns

Remove the duplicate NULL initialization for req->ns.  req->ns is always
initialized to NULL in nvmet_req_init(), so there is no need to reset
it later on failures unless we have previously assigned a value to it.

Signed-off-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

drivers/nvme/target/admin-cmd.c

@@ -548,8 +548,6 @@ u16 nvmet_parse_admin_cmd(struct nvmet_req *req)
 	struct nvme_command *cmd = req->cmd;
 	u16 ret;
 
-	req->ns = NULL;
-
 	ret = nvmet_check_ctrl_status(req, cmd);
 	if (unlikely(ret))
 		return ret;