hwmon: (tmp513) Constify struct regmap_config

`tmp51x_regmap_config` is not modified and can be declared as const to
move its data to a read-only section.

Signed-off-by: Javier Carrasco <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Guenter Roeck <[e-mail]>

drivers/hwmon/tmp513.c

···
 	TMP51X_BUS_CURRENT_RESULT
 };
 
-static struct regmap_config tmp51x_regmap_config = {
+static const struct regmap_config tmp51x_regmap_config = {
 	.reg_bits = 8,
 	.val_bits = 16,
 	.max_register = TMP51X_MAX_REGISTER_ADDR,