iwlwifi: mvm: Fix rate scale NSS configuration

The TLC configuration did not take into consideration the station's
SMPS configuration, and thus configured rates for 2 NSS even if
static SMPS was reported by the station. Fix this.

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.20200306151129.b4f940d13eca.Ieebfa889d08205a3a961ae0138fb5832e8a0f9c1@changeid