Split cargo_out into three modules.

The `cargo` module has the output types, `cargo_out` has the code
specific to parsing cargo.out files, while `metadata` has the types to
parse cargo.metadata files.

Bug: 293289578
Test: atest cargo_embargo.test
Change-Id: I5a2e2871a48bf30a64f3ffbc84a160b0daa91b53
4 files changed