arm64:loki: Disable changing brightness for LEDs

arm64:loki: Disable changing brightness for LEDs

For the center touch button, always force brightness
to be set to 255. For the function touch buttons,
in daylight, set brightness to 0 and maximum
otherwise.

Bug 1580153

Change-Id: I3359dbb6abef9ead7aecf611eb0c02a74554788e
Signed-off-by: Ankita Garg <ankitag@nvidia.com>
Reviewed-on: http://git-master/r/655061
(cherry picked from commit e8eb73047cc5f536ef9c3e9792694c7d0fc5671c)
Reviewed-on: http://git-master/r/665948
GVS: Gerrit_Virtual_Submit
Reviewed-by: Raymond Poudrier <rapoudrier@nvidia.com>