staging: rtl8723bs: Remove rtw_btcoex_HAL_Initialize()

Remove function rtw_btcoex_HAL_Initialize as it does nothing except call
hal_btcoex_InitHwConfig.
Modify call sites accordingly.
Issue found with Coccinelle.

Signed-off-by: Nishka Dasgupta <nishkadg.linux@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>