cxgb4: cleanup error code in setup_sge_queues_uld()

The caller doesn't care about the error codes, they only check for zero
vs non-zero.  Still, it's better to preserve the negative error codes
from alloc_uld_rxqs() instead of changing it to 1.  We can also return
directly if there is a failure.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>