As outlined in the PR, the aarch64 has a non-default value for
CASE_VALUES_THRESHOLD which changes decisions in switch lowering.  Those
changes in switch lowering can expose additional jump threads later in
the pipeline which cause heartburn for a couple tests.

I looked at all the other ports with a non-default value of
CASE_VALUES_THRESHOLD and only aarch64 is high enough to trigger these
changes in behavior on the two relevant tests.  So I'm just skipping the
tests that run after switch lowering on aarch64.

Verified with a cross that these tests now pass.

Committing to the trunk,

Jeff