RFR: 8335709: C2: assert(!loop->is_member(get_loop(useblock))) failed: must be outside loop

[Roland Westrelin]

When a `NeverBranch` is added to an infinite loop, the `NeverBanch`
and its projection that branches in the loop are assigned to the wrong
loop. The confuses the logic that tries to sink nodes out of loop.

-------------

Commit messages:
 - fix & test

Changes: https://git.openjdk.org/jdk/pull/20231/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=20231&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8335709
  Stats: 61 lines in 2 files changed: 58 ins; 0 del; 3 mod
  Patch: https://git.openjdk.org/jdk/pull/20231.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/20231/head:pull/20231

PR: https://git.openjdk.org/jdk/pull/20231