arch-arm: Change mcrMrc15TrapToHyp signature

arch-arm: Change mcrMrc15TrapToHyp signature

This patch is moving MiscRegs reading inside the mcrMrc15TrapToHyp
helper function. Rather than passing registers as arguments,
we are just passing a ThreadContext pointer

Change-Id: I6636dd3a4f92f757479d8a8d2c47de050a0b9eae
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/17988
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
Tested-by: kokoro <noreply+kokoro@google.com>