Rsp files are supported through helper script (gen-kotlin-build-file.sh)
that generates the kotlinc module/build xml file.
Since rsp files are supported, I've added ExtractSrcJarsCmd step
to handle srcjars extraction.
Minor reorderings to make sure that TransformKotlinToClasses
recives only .java and .kt files when called from Module.compile.
Bug: 73281388
Test: make -j hidl-doc
Change-Id: I5a40b914569018dc529903a7f2864a5aeae838e5
