Wlan firmware updates "max tx pwr allowed" to host in vdev start response
event and roam sync indication event. Host uses this value to update
power constraint ie in assoc request and TPC query response.
Host updates "max tx pwr allowed" value to firmware after association
completion, so that firmware uses the same max power to transmit mgmt and
data frames.
Change-Id: Ifd8d47fd830bd02bdde2633c22ea82820adf73a0
CRs-Fixed: 2652690