[jdk11u-dev] RFR: 8273606: Zero: SPARC64 build fails with si_band type mismatch

[Aleksey Shipilev]

Fixes the corner case in Zero/SPARC64 build. The change is no-op for the well-behaved libc.

This patch differs from the upstream, since the POSIX signal refactoring (JDK-8252324) is not in 11u. The similar old place is patched.

Additional testing:
 - [x] Linux Zero/SPARC64 cross-compilation fails without the patch, passes with the patch

-------------

Commit messages:
 - Backport 241ac89f120f9bcfef65962aa05b51b9f847c4ce

Changes: https://git.openjdk.java.net/jdk11u-dev/pull/459/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk11u-dev&pr=459&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8273606
  Stats: 5 lines in 1 file changed: 4 ins; 0 del; 1 mod
  Patch: https://git.openjdk.java.net/jdk11u-dev/pull/459.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk11u-dev pull/459/head:pull/459

PR: https://git.openjdk.java.net/jdk11u-dev/pull/459