drm/i915/display: Remove kstrdup_const() and kfree_const() usage

kstrdup_const() and kfree_const() can be confusing in code built as a
module. In such a case, it does not do what one could expect from the name
of the functions.

The code is not wrong by itself, but in such a case, it is equivalent to
kstrdup() and kfree().

So, keep thinks simple and straightforward.

This reverts commit 379b63e ("drm/i915/display: Save a few bytes of
memory in intel_backlight_device_register()")

Signed-off-by: Christophe JAILLET <[email protected]>
Link: https://patchwork.freedesktop.org/patch/msgid/f82be2ee3ac7d18dd9982b5368a88a5bf2aeb777.1727977199.git.christophe.jaillet@wanadoo.fr
Signed-off-by: Jani Nikula <[email protected]>

drivers/gpu/drm/i915/display/intel_backlight.c

@@ -949,7 +949,7 @@ int intel_backlight_device_register(struct intel_connector *connector)
 	else
 		props.power = BACKLIGHT_POWER_OFF;
 
-	name = kstrdup_const("intel_backlight", GFP_KERNEL);
+	name = kstrdup("intel_backlight", GFP_KERNEL);
 	if (!name)
 		return -ENOMEM;
 
@@ -963,7 +963,7 @@ int intel_backlight_device_register(struct intel_connector *connector)
 		 * compatibility. Use unique names for subsequent backlight devices as a
 		 * fallback when the default name already exists.
 		 */
-		kfree_const(name);
+		kfree(name);
 		name = kasprintf(GFP_KERNEL, "card%d-%s-backlight",
 				 i915->drm.primary->index, connector->base.name);
 		if (!name)
@@ -987,7 +987,7 @@ int intel_backlight_device_register(struct intel_connector *connector)
 		    connector->base.base.id, connector->base.name, name);
 
 out:
-	kfree_const(name);
+	kfree(name);
 
 	return ret;
 }