libstagefright: squash exynos4 support

commit e41cc838b6212f8711c550522e8cefc95f003a67
Author: rINanDO <drjisakh@gmail.com>
Date:   Mon Aug 10 13:56:56 2015 +0200

    stagefright: Exynos4 MPEG4 decoder should set native color format.

    Change-Id: I41bee77d48fc0b35691b94585de10269579ae789

commit a50263c53a1ecd0f75688f7042dd5e5d9badbc39
Author: Caio Schnepper <caioschnepper@gmail.com>
Date:   Wed Jun 10 22:26:07 2015 -0300

    libstagefright: back off exynos4_enhancements HWC_HWOVERLAY usage

    The open source hwc doesn't support the
    GRALLOC_USAGE_HW_FIMC1 | GRALLOC_USAGE_HWC_HWOVERLAY
    combination. Removing HWC_HWOVERLAY allows FIMC1 to do
    decode/color conversion.

    Change-Id: Ibdfa9e5dd170e99e0d994540979e88e519931641

commit 63286a333bde1aa047de4e2fde8da1b59e42a16d
Author: Ricardo Cerqueira <cyanogenmod@cerqueira.org>
Date:   Sun Nov 3 02:45:19 2013 +0000

    exynos4: libstragefright: add support for samsung colorformat/omx/mfc

    Source:
    http://git.insignal.co.kr/samsung/exynos/android/platform/frameworks/av/commit/?h=exynos-jb&id=1614612f7ca2a00473d202dbedcb135fadc608ad

    Conflicts:

        media/libstagefright/ACodec.cpp
        media/libstagefright/OMXCodec.cpp

    cherry pick from 906eba9f

    Change-Id: I1c174f8e9fa9bd3ed16a0399f070b6680f6a331c

Change-Id: I47f5b09b37ea5376a45c80c9dd91a7fbd0c3361a