sim-se,arch-riscv: Fixes file-related flags for riscv64 target

Previous file-related flags for the riscv64-unknown-linux-gnu target
do not match the actual
values, leading to incorrect behaviours in certain emulated syscalls.
This commit fixes the problem.

Change-Id: I38ff624c00e46e37672510af5a10f527b5f0842a
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/64472
Maintainer: Jason Lowe-Power <power.jg@gmail.com>
Tested-by: kokoro <noreply+kokoro@google.com>
Reviewed-by: Jason Lowe-Power <power.jg@gmail.com>
1 file changed