build: Automatically replace old-style kernel header includes with new header lib

This is a combination of 3 commits.
This is the 1st commit message:

build: add kernel header dependency if module uses kernel headers

Many of the QCOM components use kernel headers, but don't declare
the dependency on them.  This is fine in CAF because of the way they
build the boot.img before anything else.  In CM, we don't build the
boot.img the same, so we run into a race between the kernel build &
these modules... and the modules lose.

Warn about modules that have this missing dependency, and add it for
them so we don't have to modify each Android.mk.

Change-Id: I95f1e47b5ef440f6f5d8f64a0c3f38d9572e839e

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This is the commit message #2:

build: Switch kernel header inclusion

The build is switching to the target INSTALLED_KERNEL_HEADERS to
declare dependencies on kernel headers.

Change-Id: I913e74681b02dfcf1eaed3d1e47ff4ab2300b12d

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This is the commit message #3:

build: Automatically replace old-style kernel header includes with new header lib

Since we do this via soong and the result is a header library, just replace all
legacy include paths that point to the old header location with calls to the new
header library. Since we no longer have the legacy include, we can also remove
the additional dependency.

This reverts commit fa798218.

Change-Id: I716955534e50831e6568ca01e480aa8b90075d92

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This is the commit message #4:

build: Also replace techpack/audio old-style kernel header

 * We are also going to replace them by the new header lib

Change-Id: I0562d8f0cfe3186af50e00eaab858f2836cbc9f0

Change-Id: I5a0ab4438772a5981464a3013b3671352847267c