build: Squash of allowing a device to generically define its own headers

Author: Ricardo Cerqueira <cyanogenmod@cerqueira.org>
Date:   2011-04-12 10:57:22 +0100
    Allow a device to generically define its own headers

    We have a few cases of devices including specific versions of projects
    just because of modified headers (msm_mdp.h comes to mind), and I just
    had enough of ifdeffing header files for specific cases (the P990 needs
    a lot of these).
    Now... if a target defines a TARGET_SPECIFIC_HEADER_PATH, any headers in
    there will take precedence over the standard ones; for example, on the
    p990, I have

    TARGET_SPECIFIC_HEADER_PATH := device/lge/p990/include

    which makes, for example, the
    device/lge/p990/include/hardware_legacy/AudioHardwareInterface.h be
    used instead of
    hardware/libhardware_legacy/include/hardware_legacy/AudioHardwareInterface.h
    whenever a source file uses <hardware_legacy/AudioHardwareInterface.h>

    Change-Id: I41b62668b60e3f62a6ebd3738d8d2675103a81e6a

    build: fix target header overlay

    LOCAL_C_INCLUDES as defined by the makefile should be put AFTER
    the overlay includes so the overlay always takes precedence.

    Change-Id: I489b2aab6dbacd9122d834f85e07b63ed1271f07

Author: Jan Altensen <info@stricted.net>
Date:   2020-09-10 15:18:49 +0200
    soong: add TARGET_SPECIFIC_HEADER_PATH

    Change-Id: I582ae8e6e010016b33fd9b020b723e5fc2dc442b

Change-Id: I3c885fe504ce4f646001697119cffd674db9ec49