net/vmxnet3: fix dereference before null check

net/vmxnet3: fix dereference before null check

Coverity reports check_after_deref:
Null-checking rq suggests that it may be null, but it
has already been dereferenced on all paths leading to
the check.
This patch removes NULL checking of "rq" from function
vmxnet3_dev_rx_queue_reset as it is already checked against NULL
one level up the callstack (function vmxnet3_dev_clear_queues).

Coverity issue: 143468
Fixes: 5aecdc17a97d ("vmxnet3: fix stop/restart")
Cc: stable@dpdk.org
Signed-off-by: Tomasz Kulasek <tomaszx.kulasek@intel.com>
Signed-off-by: Michal Jastrzebski <michalx.k.jastrzebski@intel.com>
Reviewed-by: Ferruh Yigit <ferruh.yigit@intel.com>