iwlwifi: mvm: Fix calculation of frame length

[ Upstream commit 40a0b38d7a7f91a6027287e0df54f5f547e8d27e ]

The RADA might include in the Rx frame the MIC and CRC bytes.
These bytes should be removed for non monitor interfaces and
should not be passed to mac80211.

Fix the Rx processing to remove the extra bytes on non monitor
cases.

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.20211219121514.098be12c801e.I1d81733d8a75b84c3b20eb6e0d14ab3405ca6a86@changeid


Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>