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