Fix building tests with partial arch codegen support

Add conditionals around more code that is only used for codegen for
specific architectures, and move a few more files into the
architecture-specific codegen lists.

Tests: ART_HOST_CODEGEN_ARCHS="x86_64 mips" m -j ART_TARGET_CODEGEN_ARCHS=svelte test-art-host
Bug: 30928847
Change-Id: I0444d15e1cafe4c9b13ff78718c3b13b544270e7