RFR: 8277627: Fix copyright years in some jvmci files

Mon Jan 10 20:33:27 UTC 2022

On Fri, 7 Jan 2022 08:30:38 GMT, Emanuel Peter <duke at openjdk.java.net> wrote:

> Fixed copyright years from "xxxx, xxxx" to "xxxx" (if same year mentioned twice), according to copyright year specification.
> 
> Checked that tests are not affected.

I suggest to look on history of these files changes and update second year accordingly.
For example, `MemoryBarriers.java` was update last in 2016 based on 'Blame':
https://github.com/openjdk/jdk/commit/1d60ce77a0e169da6f1564a294f842f10e29b699

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Changes requested by kvn (Reviewer).

PR: https://git.openjdk.java.net/jdk/pull/6985