configs,stdlib,tests: Update riscvmatched-fs.py to-init

The "test-gem5-library-example-riscvmatched-fs" test, which runs
"configs/example/gem5_library/riscvmatched-fs.py", was running the
script in full. This takes a very long time. Given we already have boot
tests for RISCV, it's better to just run this configuration to just the
end of the Linux boot (significantly faster than a full OS boot). This
patch adds this feature to the config script and modifies the test to
utilize it.

Change-Id: I1e37a26aab5e9a127ebd64590be79fbc16fe53aa
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/65853
Reviewed-by: Bobby Bruce <bbruce@ucdavis.edu>
Maintainer: Bobby Bruce <bbruce@ucdavis.edu>
Tested-by: kokoro <noreply+kokoro@google.com>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/65974
2 files changed