rtw88: coex: Add C2H/H2C handshake with BT mailbox for asking HID Info

In order to recognize the gaming controller HID, make a C2H/H2C/Mailbox
handshake to collect all the connected information from BT.

Signed-off-by: Ching-Te Ku <ku920601@realtek.com>
Signed-off-by: Ping-Ke Shih <pkshih@realtek.com>
Signed-off-by: Kalle Valo <kvalo@kernel.org>
Link: https://lore.kernel.org/r/20220215004855.4098-6-pkshih@realtek.com