arch-arm: Move breakpoint/watchpoint check out of the TLB

arch-arm: Move breakpoint/watchpoint check out of the TLB

The breakpoint, watchpoint, vector catch and software step checks
have been moved from the TLB to the SelfDebug class.

This is cleaningup the TLB model which is simply asking the SelfDebug
class if there is a pending debug fault

Change-Id: I1724896b24e4728b32a6b46c5cd51cc6ef279fd7
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/31079
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
Tested-by: kokoro <noreply+kokoro@google.com>