Needed to support session reclaiming

bug: 27916039
Change-Id: I464e6db5b9bc4e83f85cb4623eeca340e1efd603

bug: 26782004
Change-Id: Ie3d9289d15446efa160550185a2d565e3be2980f

Remove from unpriv_socket_ioctls but grant each user of unpriv_socket_ioctls
use of unpriv_tty_ioctls

Bug: 26990688
Change-Id: I998e09091de5a7234ad0049758d5dad0b35722f7

Part of media security hardening

This is an intermediate step toward moving
mediadrm to a new service separate from mediaserver.
This first step allows mediadrmservice to run based
on the system property media.mediadrmservice.enable
so it can be selectively enabled on devices that
support using native_handles for secure buffers.

bug: 22990512
Change-Id: I2208c1e87a6bd8d5bfaed06b1fdcb0509c11cff2