rtw88: Use rtw_write8_set to set SYS_FUNC

rtw_write8 could modify the values that we do not want
to change, use rtw_write8_set instead to only enable the
bits of sys_func_en
Signed-off-by: Yan-Hsuan Chuang <yhchuang@realtek.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>

drivers/net/wireless/realtek/rtw88/mac.c

@@ -261,7 +261,7 @@ static int rtw_mac_init_system_cfg(struct rtw_dev *rtwdev)
 	value |= BIT_WL_PLATFORM_RST | BIT_DDMA_EN;
 	rtw_write32(rtwdev, REG_CPU_DMEM_CON, value);
 
-	rtw_write8(rtwdev, REG_SYS_FUNC_EN + 1, sys_func_en);
+	rtw_write8_set(rtwdev, REG_SYS_FUNC_EN + 1, sys_func_en);
 	value8 = (rtw_read8(rtwdev, REG_CR_EXT + 3) & 0xF0) | 0x0C;
 	rtw_write8(rtwdev, REG_CR_EXT + 3, value8);