RFR: 8325680: Uninitialised memory in deleteGSSCB of GSSLibStub.c:179

[Weijun Wang]

Add a `memset` after memory is successfully allocated.

No regression test, hard to write without a KDC.

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Commit messages:
 - the fix

Changes: https://git.openjdk.org/jdk/pull/18015/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=18015&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8325680
  Stats: 5 lines in 1 file changed: 2 ins; 0 del; 3 mod
  Patch: https://git.openjdk.org/jdk/pull/18015.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/18015/head:pull/18015

PR: https://git.openjdk.org/jdk/pull/18015