RFR: 8253118: Avoid unnecessary deopts when OSR nmethods of the same level are present.

[Vladimir Kozlov]

On Fri, 25 Sep 2020 16:05:34 GMT, Igor Veresov <iveresov at openjdk.org> wrote:

> When running with ```-XX:TieredStopAtLevel={2|3}``` the policy tried to switch to OSR method of the same level if those
> are present, which caused constant deopting. The fix is to consider only higher levels for OSR switches.

Marked as reviewed by kvn (Reviewer).

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PR: https://git.openjdk.java.net/jdk/pull/360