Always convert xsd_config module type

Modules of this type have a limited set of deps (e.g. libxml2), and they
have already been converted.

compatibility_matrix_schema is a filegroup that is used in one of the
xsd_config modules in Soong, and it has been added to the allowlist as
well.

Test: bp2build.sh
Bug: 211678537
Change-Id: Idcbafe7c8413134b9dd7abb0dee53473f3e1d2e8