iwlwifi: pcie: compare with number of IRQs requested for, not number of CPUs

When there are 16 or more logical CPUs, we request for
`IWL_MAX_RX_HW_QUEUES` (16) IRQs only as we limit to that number of
IRQs, but later on we compare the number of IRQs returned to
nr_online_cpus+2 instead of max_irqs, the latter being what we
actually asked for. This ends up setting num_rx_queues to 17 which
causes lots of out-of-bounds array accesses later on.

Compare to max_irqs instead, and also add an assertion in case
num_rx_queues > IWM_MAX_RX_HW_QUEUES.

This fixes https://bugzilla.kernel.org/show_bug.cgi?id=199551

Fixes: 2e5d4a8f

 ("iwlwifi: pcie: Add new configuration to enable MSIX")
Signed-off-by: Hao Wei Tee <angelsl@in04.sg>
Tested-by: Sara Sharon <sara.sharon@intel.com>
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>