arch-riscv: Ignore set_robust_list and get_robust_list syscalls
arch-riscv: Ignore set_robust_list and get_robust_list syscalls

Change-Id: I5a4744e5aed07337144af9f07978b83405b6695b
Reviewed-on: https://gem5-review.googlesource.com/6902
Reviewed-by: Alec Roelke <8e4f8facd4fb6c7d77135df4850f69a92e6a8660@virginia.edu>
Maintainer: Alec Roelke <8e4f8facd4fb6c7d77135df4850f69a92e6a8660@virginia.edu>

TUD-OS/gem5-dtu,TUD-OS/gem5-dtu,TUD-OS/gem5-dtu,gem5/gem5,TUD-OS/gem5-dtu,TUD-OS/gem5-dtu,gem5/gem5,gem5/gem5,gem5/gem5,TUD-OS/gem5-dtu,gem5/gem5,gem5/gem5,TUD-OS/gem5-dtu,gem5/gem5