RFR: 8318889: C2: add bailout after assert Bad graph detected in build_loop_late

[Emanuel Peter]

Ensure we do not crash with SIGSEGV in product mode where we do not assert.
The check is very cheap, and a bailout an adequate solution.
In debug, we still assert and can fix the bug.

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Commit messages:
 - 8318889

Changes: https://git.openjdk.org/jdk/pull/16375/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=16375&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8318889
  Stats: 8 lines in 1 file changed: 6 ins; 2 del; 0 mod
  Patch: https://git.openjdk.org/jdk/pull/16375.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/16375/head:pull/16375

PR: https://git.openjdk.org/jdk/pull/16375