iwlwifi: mvm: BT Coex - add reduced Tx power thresholds to constants

This really belongs to the constants file.

Reviewed-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>

diff --cc drivers/net/wireless/iwlwifi/mvm/coex.c
Simple merge

diff --cc drivers/net/wireless/iwlwifi/mvm/constants.h
Simple merge