RFR: JDK-8275703: System.loadLibrary fails on Big Sur for libraries hidden from filesystem

[Mandy Chung]

On, macOS 11.x, system libraries are loaded from dynamic linker cache.  The libraries are no longer present on the filesystem.   `NativeLibraries::loadLibrary` checks for the file existence before calling `JVM_LoadLibrary`.   Such check no longer applies on Big Sur.   This proposes that on macOS >= 11, it will skip the file existence check and attempt to load a library for each path from java.library.path and system library path.

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Commit messages:
 - trim whitespaces
 - add copyright header
 - fix typo
 - JDK-8275703: System.loadLibrary fails on Big Sur for libraries hidden from filesystem

Changes: https://git.openjdk.java.net/jdk/pull/6127/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=6127&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8275703
  Stats: 198 lines in 9 files changed: 170 ins; 2 del; 26 mod
  Patch: https://git.openjdk.java.net/jdk/pull/6127.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/6127/head:pull/6127

PR: https://git.openjdk.java.net/jdk/pull/6127