iwlwifi: mvm: tighten BAID range check

As pointed out by smatch, checking the BAID for just >= INVALID
is a bad idea since only 32 (IWL_MAX_BAID) actually exist. Check
the range for that and print invalid ones in the warning.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>