iwlwifi: mvm: fix the coex firmware API

The firmware API defined in the header files didn't match
the structure that are actually passed by the firmware.
The impact could be a decision for MIMO in Tx or Rx in
coex scenarios.

Fixes: 430a3bba ("iwlwifi: mvm: BT Coex - new API")
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>