[jdk11u-dev] RFR: 8263068: Rename safefetch.hpp to safefetch.inline.hpp

[Vladimir Kempik]

Please review this simple backport to jdk11u.
it's not applying clean due to the miss of zgc in 11 and small context code difference.
This just renames safefetch.hpp file without touching any actual code.
Follow up of JDK-8261075.

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Commit messages:
 - 8263068: Rename safefetch.hpp to safefetch.inline.hpp

Changes: https://git.openjdk.java.net/jdk11u-dev/pull/543/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk11u-dev&pr=543&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8263068
  Stats: 11 lines in 9 files changed: 0 ins; 0 del; 11 mod
  Patch: https://git.openjdk.java.net/jdk11u-dev/pull/543.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk11u-dev pull/543/head:pull/543

PR: https://git.openjdk.java.net/jdk11u-dev/pull/543