[lldb][test] Enable non-address bit WritePointerToMemory test on Linux (#157435)

First added in #153585 for Darwin only. All Linux AArch64 systems also
have Top Byte Ignore enabled in userspace so the test "just works"
there.

FreeBSD has very recently gained Top Byte Ignore support:
https://github.com/freebsd/freebsd-src/commit/4c6c27d3fb4ad15931aae2eaf8e624aed99a3fd9

However it's so recent, I don't want to assume it'll be available on any
random FreeBSD system out there.

There isn't really a good place to put this test, so I put it in the top
level of API, next to the other non-address bit test that didn't have a
good home either.

GitOrigin-RevId: b21dd44dbc00a60b787dcfa90ca0e8b677c5211f
4 files changed