wifi: iwlwifi: pcie: fix NULL pointer dereference in iwl_pcie_irq_rx_msix_handler()

rxq can be NULL only when trans_pcie->rxq is NULL and entry->entry
is zero. For the case when entry->entry is not equal to 0, rxq
won't be NULL even if trans_pcie->rxq is NULL. Modify checker to
check for trans_pcie->rxq.

Fixes: abc599ef

 ("iwlwifi: pcie: don't crash when rx queues aren't allocated in interrupt")
Signed-off-by: Anjaneyulu <pagadala.yesu.anjaneyulu@intel.com>
Signed-off-by: Gregory Greenman <gregory.greenman@intel.com>
Link: https://lore.kernel.org/r/20230614123446.5a5eb3889a4a.I375a1d58f16b48cd2044e7b7caddae512d7c86fd@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>