Revert "Revert "arm64: expand CFI shadow to cover 48-bit virtual addresses""

This reverts commit ea3df0c5, and
increases the address limit on non-aarch64 64-bit platforms as well.

RLIMIT_AS problem fixed in a different commit.

Bug: 63141434, 64293803
Test: device boots
Change-Id: I1284c4196cc1f0c9d97c3ced97a19de328050d21