util: Add a crosstool-ng defconfig for RISCV.

This may have been available before as well, but it was hidden behind an
"experimental" flag which needed to be enabled before riscv was
selectable.

Change-Id: I76239d826163e54d0b8a48c3492930bb787bea02
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/41453
Tested-by: kokoro <noreply+kokoro@google.com>
Maintainer: Gabe Black <gabe.black@gmail.com>
Maintainer: Bobby R. Bruce <bbruce@ucdavis.edu>
Reviewed-by: Bobby R. Bruce <bbruce@ucdavis.edu>
1 file changed