RFR: 8277627: Fix copyright years in some jvmci files [v2]

[Emanuel Peter]

> Fixed copyright years from "xxxx, xxxx" to "xxxx" (if same year mentioned twice), according to copyright year specification.
> Updated the second year (last edit) where missing.
> 
> Checked that tests are not affected.

Emanuel Peter has updated the pull request incrementally with one additional commit since the last revision:

  Checked for latest edit year, added it into copyright where missing

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

Changes:
  - all: https://git.openjdk.java.net/jdk/pull/6985/files
  - new: https://git.openjdk.java.net/jdk/pull/6985/files/b9749b44..2244436a

Webrevs:
 - full: https://webrevs.openjdk.java.net/?repo=jdk&pr=6985&range=01
 - incr: https://webrevs.openjdk.java.net/?repo=jdk&pr=6985&range=00-01

  Stats: 8 lines in 8 files changed: 0 ins; 0 del; 8 mod
  Patch: https://git.openjdk.java.net/jdk/pull/6985.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/6985/head:pull/6985

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