Make libbinder_rs vendor available.

Add vendor_available: true to libbinder_rs and dependencies.
Also remove set_requesting_sid conditionally if building the vendor
variant.

Test: Vendor components can compile and link against libbinder_rs.
Bug: 198197213
Change-Id: I9ad9ed226e76c16bff7d3feb201fd9fef20ad934
4 files changed