wifi: iwlwifi: mvm: fix EOF bit reporting

wifi: iwlwifi: mvm: fix EOF bit reporting

In monitor mode, we try to report the EOF bit on the
first MPDU of an A-MPDU (hardware duplicates this bit
over all MPDUs, so it's only trustable on the first).

However, due to reshuffling in an ealier commit, the
toggle_bit != mvm->ampdu_toggle logic can no longer
work since mvm->ampdu_toggle is now set before this
code runs.

Fix this by tracking the first_subframe status in the
phy data struct and using that instead of checking.

Fixes: f1490546bec9 ("wifi: iwlwifi: mvm: rxmq: refactor mac80211 rx_status setting")
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Gregory Greenman <gregory.greenman@intel.com>
Link: https://lore.kernel.org/r/20230305124407.e273aa0d3fdc.I77db4cc247898eae8a98b80659386d6737052b95@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>