Allow platform modules to link to vendor public libraries

Normally, when building with VNDK, platform modules are not allowed to
link against vendor libraries, because the ABI of the vendor libraries
are not guaranteed to be stable and may differ across multiple vendor
images.

However, the vendor public libraries are the exceptions. Vendor public
libraries are vendor libraries that are exposed to 3rd party apps and
listed in /vendor/etc/public.libraries.txt. Since they are intended to
be exposed to public, their ABI stability is guaranteed (by definition,
though it is up to the vendor to actually guarantee it).

This change allows platform modules to link to vendor public libraries.
When the name of a vendor public libraries (whose stub is defined via
vendor_public_library in Android.bp) is listed in
LOCAL_SHARED_LIBRARIES, it is actually linked to the stub library which
is available to platform modules.

Bug: 74275385
Test: m -j
Merged-In: I063b43431196190b59332b1bcad59f267073f89f
Change-Id: I063b43431196190b59332b1bcad59f267073f89f
(cherry picked from commit c3f1356a)