Add dist goal for module-info.json

Per user request. Unbundled builds (like mainline builds) can now run
`m module-info dist` to dist module-info.json and
module_bp_java_deps.json without building unnecessary artifacts.

Test: aninja -t query _dist_module-info
Change-Id: I0ad78d040f0b95c20f4fad8736febe7853d02b3c