RFR: 8267721: Enable sun/security/pkcs11 tests for Amazon Linux 2 AArch64

[Evgeny Astigeevich]

Tests sun/security/pkcs11 are skipped on AArch64 Linux when they cannot find NSS libraries in one of the directories {'/usr/lib/aarch64-linux-gnu/', '/usr/lib/aarch64-linux-gnu/nss/'}. On Amazon Linux 2 the libraries are in /usr/lib64. 

This patch adds '/usr/lib64' to the search list of directories.
Test:
- Before the patch

$ make run-test TEST=sun/security/pkcs11
$ cd build
$ find . -name '*.jtr' -exec grep 'find NSS' {} ; | wc -l
129

- After the patch

$ make run-test TEST=sun/security/pkcs11
$ cd build
$ find . -name '*.jtr' -exec grep 'find NSS' {} ; | wc -l
0

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

Commit messages:
 - 8267721: Enable sun/security/pkcs11 tests for Amazon Linux 2 AArch64

Changes: https://git.openjdk.java.net/jdk/pull/4207/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=4207&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8267721
  Stats: 2 lines in 1 file changed: 1 ins; 0 del; 1 mod
  Patch: https://git.openjdk.java.net/jdk/pull/4207.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/4207/head:pull/4207

PR: https://git.openjdk.java.net/jdk/pull/4207