RFR: 8371385: compiler/escapeAnalysis/TestRematerializeObjects.java fails in case of -XX:-UseUnalignedAccesses

[Fei Yang]

Hi, Please consider this small change fixing a test failure.

Two IR rules failed under -XX:-EliminateAllocations on platforms with -XX:-UseUnalignedAccesses.
These are expecting MergeStores to combine and emit StoreL or StoreI. But the enablement of MergeStores
depends on flag UseUnalignedAccesses [1]. So this simply add that condition to applyIf of the two IR rules.

[1] https://github.com/openjdk/jdk/blob/master/src/hotspot/share/opto/memnode.cpp#L3455

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Commit messages:
 - 8371385: compiler/escapeAnalysis/TestRematerializeObjects.java fails in case of -XX:-UseUnalignedAccesses

Changes: https://git.openjdk.org/jdk/pull/28171/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=28171&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8371385
  Stats: 4 lines in 1 file changed: 0 ins; 0 del; 4 mod
  Patch: https://git.openjdk.org/jdk/pull/28171.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/28171/head:pull/28171

PR: https://git.openjdk.org/jdk/pull/28171