mfd: rtsx: Add set pull control macro and simplify rtl8411

Add set pull control macro to reduce code for setting pull control, and
use a common init function to reduce code for rtl8411.c. So this patch
is used to just simplify code.

Signed-off-by: Micky Ching <micky_ching@realsil.com.cn>
Reviewed-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>