sepolicy: Merge local sysfs_led into global sysfs_leds.

Global sysfs_leds type was introduced lately (commit
62aee3b41b30151eee5a3eb1b3a95efaa329d94c in platform/system/sepolicy).
This CL merges the angler specific sysfs_led type into sysfs_leds, which
also fixes the denial for recovery (because recovery has the sysfs_leds
access permission only).

Bug: 35877757
Test: Flash on angler; can change backlight brightness from system UI;
      no related SELinux denials.
Test: Boot into recovery and verify recovery can set brightness.
Change-Id: Ibfd6768af8285a7e69b6417d057e3706119afab4
5 files changed