Torch: Switch to sysfs interface

Change-Id: I81f5aacda1fd3237a0dfe8d7bd65090730c04a83
ril: Ignore unsupported IMS state request

These requests are left dangling, return an explicit not-supported
reply to avoid timeouts

Change-Id: I5ddecf43e112c64ea719c5b753993b5b8f0d5dde
enable sf optimizations for virtual displays

Change-Id: I5469e2591074e76b3d596af8b5928b5854df6ca7