iwlwifi: mvm: Add support for a new version of scan request command

The scan request command is identical in binary format to the previous
scan request command and the only change is now a previously reserved
octet is used to indicate new flags introduced in the command. Align
the code to support the new version and the previous one.

Later patches would add the specific handling for the new
flags.

Signed-off-by: Ilan Peer <ilan.peer@intel.com>
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
Link: https://lore.kernel.org/r/iwlwifi.20211204130722.392a4af559bc.Ib8f1e3b527453531c10bfd7f4b116d3e257c7f1f@changeid


Signed-off-by: Luca Coelho <luciano.coelho@intel.com>