[PATCH] nbd: Drop dead code spotted by Coverity

[Eric Blake]

CID 1488362 points out that the second 'rc >= 0' check is now dead
code.

Reported-by: Peter Maydell <peter.maydell@linaro.org>
Fixes: 172f5f1a40(nbd: remove peppering of nbd_client_connected)
Signed-off-by: Eric Blake <eblake@redhat.com>
---
 block/nbd.c | 8 ++------
 1 file changed, 2 insertions(+), 6 deletions(-)

diff --git a/block/nbd.c b/block/nbd.c
index 6085ab1d2c..7f5f50ec46 100644
--- a/block/nbd.c
+++ b/block/nbd.c
@@ -521,12 +521,8 @@ static int coroutine_fn 
nbd_co_send_request(BlockDriverState *bs,
     if (qiov) {
         qio_channel_set_cork(s->ioc, true);
         rc = nbd_send_request(s->ioc, request);
-        if (rc >= 0) {
-            if (qio_channel_writev_all(s->ioc, qiov->iov, qiov->niov,
-                                       NULL) < 0) {
-                rc = -EIO;
-            }
-        } else if (rc >= 0) {
+        if (rc >= 0 && qio_channel_writev_all(s->ioc, qiov->iov, qiov->niov,
+                                              NULL) < 0) {
             rc = -EIO;
         }
         qio_channel_set_cork(s->ioc, false);
-- 
2.36.1