aarch64: Prefer register ranges & support wrapping

aarch64: Prefer register ranges & support wrapping

Until now, binutils has supported register ranges such
as { v0.4s - v3.4s } as an unofficial shorthand for
{ v0.4s, v1.4s, v2.4s, v3.4s }.  The SME2 ISA embraces this form
and makes it the preferred disassembly.  It also embraces wrapped
lists such as { z31.s - z2.s }, which is something that binutils
didn't previously allow.

The range form was already binutils's preferred disassembly for 3- and
4-register lists.  This patch prefers it for 2-register lists too.
The patch also adds support for wrap-around.