clean up Makefiles

- Remove libchrome from top-level Makefile since not every component
  needs to link against it.
- Replace local Android include paths with pkgconfig cflags from the
  arc-camear3-android-headers package.

BUG=b:36919374
CQ-DEPEND=CL:538538
TEST=Make sure all the arc-camera3* packages build.
TEST=`FEATURES=test emerge-poppy arc-camera3 arc-camera3-libcbm`

Change-Id: I959362c3b4e5c0805089d60c309b51d0cdf7d6d1
Reviewed-on: https://chromium-review.googlesource.com/538413
Commit-Ready: Ricky Liang <jcliang@chromium.org>
Tested-by: Ricky Liang <jcliang@chromium.org>
Reviewed-by: Ricky Liang <jcliang@chromium.org>
8 files changed