Use vndk snapshot libraries txt files if exist

For the trunk stable next build, we have duplicated modules for the
vndk libraries txt files: one from the generated list, the other from
the prebuilt vndk snapshot files.
If the current vndk version provided by the vndk snapshots, use the
txt file from the prebuilt vndk snapshot.

Bug: 296777146
Test: lunch cf_x86_64_phone-next-userdebug && m nothing
Change-Id: I18bd7b7c77bd37c26c5e0b15cb020a59d50f4f2f