wcn36xx: Functionally decompose wcn36xx_smd_config_sta()

This commit functionally decomposes wcn36xx_smd_config_sta into a clearly
defined wcn36xx_smd_config_sta_v0 and wcn36xx_smd_config_sta_v1 path.

Signed-off-by: Bryan O'Donoghue <bryan.odonoghue@linaro.org>
Reviewed-by: Loic Poulain <loic.poulain@linaro.org>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20200910150631.2178970-2-bryan.odonoghue@linaro.org