arch-arm: Enable Debug IFSC when faulting to aarch64 mode
Previous code was aborting simulation when a debug exception taken in
aarch64 mode was encountered. This because an invalid (0xff)
instruction fault status code was produced.
Change-Id: I289f93f672be70cfbdc404be536809835160bdaf
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/8363
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>