arch-arm: updateMiscReg not setting isHyp in aarch64

arch-arm: updateMiscReg not setting isHyp in aarch64

The isHyp flag should be set for a TLB::NormalTran when in EL2.  This
was happening in aarch32 only, where the CPSR mode is checked, while
aarch64 was only using it for explicit EL2 translations, like for AT
instructions.

Change-Id: I54605811e9dde75b5cf8868190b0f4c2a8d46570
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/18394
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
Tested-by: kokoro <noreply+kokoro@google.com>