RFR: 8316125: Windows call_stub unnecessarily saves xmm16-31 when UseAVX>=3

[Daniel Jeliński]

Please review this patch that removes saving of xmm16-xmm31 registers from Windows call_stub.

Windows ABI only mandates saving xmm6-xmm15, which we continue to do here.

No new tests. Mach5 tier1-5 builds and tests clean.

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Commit messages:
 - Use AVX(1) instructions for register saving
 - Stop saving xmm16-31 in Windows call_stub

Changes: https://git.openjdk.org/jdk/pull/15688/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=15688&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8316125
  Stats: 26 lines in 3 files changed: 0 ins; 17 del; 9 mod
  Patch: https://git.openjdk.org/jdk/pull/15688.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/15688/head:pull/15688

PR: https://git.openjdk.org/jdk/pull/15688