platform: generic-arm64: Map MMIO addresses with GUARD am: 4dddb6a2d6

Original change: https://android-review.googlesource.com/c/trusty/lk/trusty/+/3402739

Change-Id: I5e39ebce67733fd917fe2c9e045b67100aa7bfef
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>