wifi: ath11k: Relocate the func ath11k_mac_bitrate_mask_num_ht_rates() and...

wifi: ath11k: Relocate the func ath11k_mac_bitrate_mask_num_ht_rates() and change hweight16 to hweight8

Relocate the function ath11k_mac_bitrate_mask_num_ht_rates() definition
to call this function from other functions which helps to avoid the
compilation error (function not defined).

ht_mcs[] is 1 byte array and it is enough to use hweight8() instead
of hweight16(). Hence, fixed the same.

Tested on: Compile tested only.

Signed-off-by: Maharaja Kennadyrajan <quic_mkenna@quicinc.com>
Signed-off-by: Kalle Valo <quic_kvalo@quicinc.com>
Link: https://lore.kernel.org/r/20230504092033.3542456-2-quic_mkenna@quicinc.com