Remove libnativehelper directories from include_dirs

Uses libnativehelper_header_only library headers instead.

Needed as libnativehelper is part of the runtime module and so will not
be present in an unbundled build, instead its build targets will be
provided as prebuilts.

Bug: 134379140
Test: m checkbuild
Change-Id: I8becbda3a202ddaed52eaf861ac94fe4b08807c2