device: Constify struct device * parameter to dev_name

dev_name() does not need to modify the device structure. Hence, this
change makes the struct device * parameter to dev_name() as const.

Change-Id: I6a94394385e45fd76f68218bf57914bddd2e2121
Signed-off-by: Furquan Shaikh <furquan@google.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/40703
Reviewed-by: HAOUAS Elyes <ehaouas@noos.fr>
Reviewed-by: Aaron Durbin <adurbin@chromium.org>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

src/device/device_util.c

@@ -225,7 +225,7 @@ const char *dev_path(const struct device *dev)
 	return buffer;
 }
 
-const char *dev_name(struct device *dev)
+const char *dev_name(const struct device *dev)
 {
 	if (dev->name)
 		return dev->name;