iwlwifi: mvm: radiotap: remove UL_DL bit in HE TRIG_BASED

UL_DL is irrelevant to HE TRIG_BASED PPDU.

Signed-off-by: Shaul Triebitz <shaul.triebitz@intel.com>
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>