RFR: 8272330: C2: Cleanup profile counter scaling

[Igor Veresov]

Confusing computation during profile counter scaling was left as vestige of the old compilation policy. Clean it up.

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Commit messages:
 - Cleanup profile counter scaling

Changes: https://git.openjdk.java.net/jdk/pull/5087/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=5087&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8272330
  Stats: 10 lines in 1 file changed: 2 ins; 3 del; 5 mod
  Patch: https://git.openjdk.java.net/jdk/pull/5087.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/5087/head:pull/5087

PR: https://git.openjdk.java.net/jdk/pull/5087