rtw88: coex: update coex parameter to improve A2DP quality

Update COEX parameters and logic to enhance WL/BT performance
while WL_Busy + A2DP in a less interference environment.
It can avoid the interference comes cross from each other
and earned more performance.

Signed-off-by: Ching-Te Ku <ku920601@realtek.com>
Signed-off-by: Ping-Ke Shih <pkshih@realtek.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20201109085909.9143-3-pkshih@realtek.com