iwlwifi: pcie: add rx packet sequence number to dbg print

For each RX packet until this patch there only was a debug
print of the HCMD and the offset. This adds also the
sequence number of the packet for easier matching between
what was sent, what came back / was received, and what
got stuck somewhere and was never responded by the FW.

Signed-off-by: Liad Kaufman <liad.kaufman@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>