[jdk17u-dev] RFR: 8293232: Fix race condition in pkcs11 SessionManager

[zzambers]

Backport - fix for race condition in pkcs11 SessionManager.

Applied cleanly. Passed jdk_security tests.

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Commit messages:
 - Backport 1e031e6a5886fba3009d8e5fa62416fe15a901b6

Changes: https://git.openjdk.org/jdk17u-dev/pull/705/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk17u-dev&pr=705&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8293232
  Stats: 7 lines in 1 file changed: 5 ins; 0 del; 2 mod
  Patch: https://git.openjdk.org/jdk17u-dev/pull/705.diff
  Fetch: git fetch https://git.openjdk.org/jdk17u-dev pull/705/head:pull/705

PR: https://git.openjdk.org/jdk17u-dev/pull/705