RFR: 8314262: GHA: Cut down cross-compilation sysroots deeper

[Erik Joelsson]

On Tue, 15 Aug 2023 12:36:05 GMT, Aleksey Shipilev <shade at openjdk.org> wrote:

> [JDK-8294941](https://bugs.openjdk.org/browse/JDK-8294941) cut out some unused files in GHA sysroots. But I notice that even after that, we still have quite a bit of fluff there, especially in RISC-V sysroot. We can cut a bit deeper. Notably, we don't need runnable gcc in the sysroot, because we use the cross-compilation toolchain from the host.
> 
> This further saves bandwidth, cache size, etc. for actively developed projects.
> 
> Seeing the following improvements in sysroot sizes:
> 
> 
>  ARM: 64 MB -> 37 MB
>  AArch64:  80 MB -> 46 MB
>  S390X: 69 MB -> 41 MB
>  PPC64: 84 MB -> 51 MB
>  RISC-V: 287 MB -> 53 MB
> 
> Total: 584 MB -> 228 MB (-61%)
> 
> 
> Additional testing:
>  - [x] GHA (cross-builds still work fine)

Marked as reviewed by erikj (Reviewer).

-------------

PR Review: https://git.openjdk.org/jdk/pull/15287#pullrequestreview-1578536157