wcn36xx: Add wcn36xx_smd_set_bss_vht_params()

This commit adds wcn36xx_smd_set_bss_vht_params(). The job of this function
is to decide if the BSS is VHT capable and if so set the appropriate bit
in the BSS parameter structure for passing to the firmware.

VHT Channel width set is not set since we don't support 160MHz.

Signed-off-by: Bryan O'Donoghue <bryan.odonoghue@linaro.org>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20200910150552.2178882-7-bryan.odonoghue@linaro.org