This commit marks libselinux.so as VNDK, so that vendor variant of
libselinux.so can be installed into /system/lib[64]/vndk instead of
/vendor/lib[64]. This makes it easier to apply security patches
through system-only OTAs.
Before this commit, libselinux was not an VNDK library because there
was a concern with selabel database file format. This is no longer a
concern because the file backend is disabled in vendor variant.
Bug: 69587962
Bug: 63866913
Test: /system/lib64/vndk/libselinux.so shows up in GSI
Change-Id: I9d3be760bb5b3f8bf50b96ce6d8b938bf75c620a
Needed to allow Android to keep building with a copy of the SELinux
source code checked into external/selinux
Bug: 19963152
Change-Id: I4e192bb6ca5d185e11540aca7253e729d92a00c1
