rtw89: use inline function instead macro to set H2C and CAM

In order to use compiler to check if we do improper cast of const* on
arguments of inline function.

Signed-off-by: Ping-Ke Shih <pkshih@realtek.com>
Tested-by: Takashi Iwai <tiwai@suse.de>
Tested-by: Larry Finger <Larry.Finger@lwfinger.net>
Signed-off-by: Kalle Valo <kvalo@kernel.org>
Link: https://lore.kernel.org/r/20211119054512.10620-4-pkshih@realtek.com