gpu: host1x: Stop open-coding of_device_uevent()

There is apparently no reasons to open-code of_device_uevent() besides:
- The helper receives a struct device while we want to use the of_node
  member of the struct device *parent*.
- of_device_uevent() could not be called by modules because of a missing
  EXPORT_SYMBOL*().

In practice, the former point is not very constraining, just calling
of_device_uevent(dev->parent, ...) would have made the trick.

The latter point is more an observation rather than a real blocking
point because nothing prevented of_uevent() (called by the inline
function of_device_uevent()) to be exported to modules. In practice,
this helper is now exported, so nothing prevent us from using
of_device_uevent() anymore.

Let's use the core helper directly instead of open-coding it.

Cc: Thierry Reding <thierry.reding@gmail.com>
Cc: David Airlie <airlied@gmail.com>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Mikko Perttunen <mperttunen@nvidia.com>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: Frank Rowand <frowand.list@gmail.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230622213214.3586530-3-miquel.raynal@bootlin.com

drivers/gpu/host1x/bus.c

@@ -338,32 +338,15 @@ static int host1x_device_match(struct device *dev, struct device_driver *drv)
 	return strcmp(dev_name(dev), drv->name) == 0;
 }
 
+/*
+ * Note that this is really only needed for backwards compatibility
+ * with libdrm, which parses this information from sysfs and will
+ * fail if it can't find the OF_FULLNAME, specifically.
+ */
 static int host1x_device_uevent(const struct device *dev,
 				struct kobj_uevent_env *env)
 {
-	struct device_node *np = dev->parent->of_node;
-	unsigned int count = 0;
-	struct property *p;
-	const char *compat;
-
-	/*
-	 * This duplicates most of of_device_uevent(), but the latter cannot
-	 * be called from modules and operates on dev->of_node, which is not
-	 * available in this case.
-	 *
-	 * Note that this is really only needed for backwards compatibility
-	 * with libdrm, which parses this information from sysfs and will
-	 * fail if it can't find the OF_FULLNAME, specifically.
-	 */
-	add_uevent_var(env, "OF_NAME=%pOFn", np);
-	add_uevent_var(env, "OF_FULLNAME=%pOF", np);
-
-	of_property_for_each_string(np, "compatible", p, compat) {
-		add_uevent_var(env, "OF_COMPATIBLE_%u=%s", count, compat);
-		count++;
-	}
-
-	add_uevent_var(env, "OF_COMPATIBLE_N=%u", count);
+	of_device_uevent(dev->parent, env);
 
 	return 0;
 }