[lworld] RFR: 8255522: [lworld] References to biased pattern remain in markWord::is_unlocked()

[David Simms]

* more gtest mark word tests
* assert any use of "biased locking" (there are some existing "has_biased_pattern()" asserts not guarded "UseBiasedLocking")
* remove biased_lock_mask_in_place from is_unlocked

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Commit messages:
 - More unguarded biased locking
 - 8255522: [lworld] References to biased pattern remain in markWord::is_unlocked()

Changes: https://git.openjdk.java.net/valhalla/pull/245/files
 Webrev: https://webrevs.openjdk.java.net/?repo=valhalla&pr=245&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8255522
  Stats: 147 lines in 10 files changed: 134 ins; 1 del; 12 mod
  Patch: https://git.openjdk.java.net/valhalla/pull/245.diff
  Fetch: git fetch https://git.openjdk.java.net/valhalla pull/245/head:pull/245

PR: https://git.openjdk.java.net/valhalla/pull/245