mfd: stw481x: Staticize stw481x_regmap_config

stw481x_regmap_config is local to this file.

Acked-by: Linus Walleij <[e-mail]>
Signed-off-by: Sachin Kamat <[e-mail]>
Signed-off-by: Lee Jones <[e-mail]>

drivers/mfd/stw481x.c

···
 	},
 };
 
-const struct regmap_config stw481x_regmap_config = {
+static const struct regmap_config stw481x_regmap_config = {
 	.reg_bits = 8,
 	.val_bits = 8,
 };