[media] rc-core: remove generic scancode filter

The generic scancode filtering has questionable value and makes it
impossible to determine from userspace if there is an actual
scancode hw filter present or not.

So revert the generic parts.

Based on a patch from James Hogan <james.hogan@imgtec.com>, but this
version also makes sure that only the valid sysfs files are created
in the first place.

Signed-off-by: David Härdeman <david@hardeman.nu>
Acked-by: James Hogan <james.hogan@imgtec.com>
Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>
diff --git a/include/media/rc-core.h b/include/media/rc-core.h
index 6dbc7c1..fde142e 100644
--- a/include/media/rc-core.h
+++ b/include/media/rc-core.h
@@ -60,6 +60,7 @@
 /**
  * struct rc_dev - represents a remote control device
  * @dev: driver model's view of this device
+ * @sysfs_groups: sysfs attribute groups
  * @input_name: name of the input child device
  * @input_phys: physical path to the input child device
  * @input_id: id of the input child device (struct input_id)
@@ -117,6 +118,7 @@
  */
 struct rc_dev {
 	struct device			dev;
+	const struct attribute_group	*sysfs_groups[5];
 	const char			*input_name;
 	const char			*input_phys;
 	struct input_id			input_id;