Include the LOCAL_REQUIRED_MODULES when packaging.

When building test modules, dependencies added by the test modules get
build but don't get included in the packaged tests .zip file.

When packaging modules into a .zip file, this patch includes the modules
explicitly listed as a dependency in LOCAL_REQUIRED_MODULES for the
requested modules to package.

If these LOCAL_REQUIRED_MODULES dependencies are not used in the base
system image, they were build as part of the "tests" target but weree
not included in the package nor in the system image. This patch includes
those modules, making it easier to define dependencies of a test
module in the Android.mk file that defined said module, instead of
requiring to re-list all the dependent modules when packaging test
modules.

Bug: 27348226

Change-Id: Ic6f60cf2916b3fae0fa39f84aee8a4f440af9539