mfd: rtsx: Fix sparse non static symbol warning

Fixes the following sparse warning:

drivers/mfd/rtl8411.c:473:6: warning:
 symbol 'rtl8411_init_common_params' was not declared. Should it be static?

Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
diff --git a/drivers/mfd/rtl8411.c b/drivers/mfd/rtl8411.c
index ada38ad..fdd34c8 100644
--- a/drivers/mfd/rtl8411.c
+++ b/drivers/mfd/rtl8411.c
@@ -470,7 +470,7 @@
 	0,
 };
 
-void rtl8411_init_common_params(struct rtsx_pcr *pcr)
+static void rtl8411_init_common_params(struct rtsx_pcr *pcr)
 {
 	pcr->extra_caps = EXTRA_CAPS_SD_SDR50 | EXTRA_CAPS_SD_SDR104;
 	pcr->num_slots = 2;