gta4xl-common: sepolicy: Attach vendor_property_type to properties

We are going to enforce that each property has an explicit owner, such
as system, vendor, or product. This attaches vendor_property_type to
properties defined under vendor sepolicy directories.

Bug: 159097992
Test: m selinux_policy && boot device
Change-Id: I33c40ca345365d8f01f43d3ce7f1f3434b1edfd5
1 file changed