RFR: 8325937: runtime/handshake/HandshakeDirectTest.java causes "monitor end should be strictly below the frame pointer" assertion failure on AArch64

[Coleen Phillimore]

Add missing StoreLoad fences in handshaking code to match safepoint code.  Thanks to @pchilano for finding this bug.

Tested with tier1-4 and tier8 which has Kitchensink in it.

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Commit messages:
 - 8325937: runtime/handshake/HandshakeDirectTest.java causes "monitor end should be strictly below the frame pointer" assertion failure on AArch64

Changes: https://git.openjdk.org/jdk/pull/21295/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=21295&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8325937
  Stats: 8 lines in 1 file changed: 7 ins; 0 del; 1 mod
  Patch: https://git.openjdk.org/jdk/pull/21295.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/21295/head:pull/21295

PR: https://git.openjdk.org/jdk/pull/21295