bp2build for cc libraries that use xsd_config as gen srcs

In Soong, cc libraries depend on source files generated from xsd_config
using generated_sources and generated_headers. In Bazel, these souces
will be wrapped in a static library. Updated bp2build so that these are
written to implementation_whole_archive_deps instead.

Bug: 211678537
Test: bp2build test in sibling CL in system/tools/xsdc
Change-Id: Ib57c563a1eb7483bd7b04ba0d3852ecac17cde6c