set unused attribute for unused variables

Summary: Fixes build with clang and Werror

Test Plan: verified

Reviewers: randall.rushing, synergy

Reviewed By: synergy

Differential Revision: http://review.codefirex.com/D136
QCamera3: HAL2: support using qcom display obj copied headers

Fixes hammerhead build

Change-Id: I5d847acdb841d498d29d05b44e5abe2ee7360603
Remove include <linux/android_pmem.h>

Summary:
This file is not needed and does not exist in the uapi kernel headers.

Change-Id: I7994bfeda07e094f2674a77400390240f361e8d1

Test Plan: verified, part of a big changeset coming up

Reviewers: randall.rushing, jriordan001

Differential Revision: http://review.codefirex.com/D240
HAL3: cleanup unreachable conditionals

Test Plan: gtg

Reviewers: randall.rushing, jriordan001, anders3408, synergy

Reviewed By: synergy

Differential Revision: http://review.codefirex.com/D485
Revert "Revert "Revert "Camera3: Work around for streams with different o/p rates"""

This reverts commit 2eb35a06d1a3767ea598ecc7e58fa58fe81fd91f.