Remove /vendor/default.prop

Contents that were in /vendor/default.prop are now in /vendor/build.prop

The content is placed at the top of build.prop to keep the existing
order between default.prop and builld.prop.

Bug: 117892318
Test: TH passes
Test: inspect  /vendor/build.prop and check if it has contents from
the old /vendor/default.prop file

Change-Id: Ifa1f1dca3b4f4a5fa87d26b8ee058ee706dc54bb