[mimalloc] update to 2.2.6

[miyanyan]

• Changes comply with the maintainer guide.
• SHA512s are updated for each updated download.
• The "supports" clause reflects platforms that may be fixed by this new version.
• Any fixed CI baseline entries are removed from that file.
• Any patches that are no longer applied are deleted from the port's directory.
• The version database is fixed by rerunning ./vcpkg x-add-version --all and committing the result.
• Only one version is added to each modified port's versions file.

[miyanyan]

https://github.com/microsoft/mimalloc/tags
There are three new tags 3.2.6 2.2.6 1.9.6, how to maintain the different versions?
Currently there is only V2

[talregev]

you should always be on the latest as possible.
There is other port that needed mimalloc?
If yes, try to upgrade to version 3, and be on it.
If no, it more easy to go to version 3.

[dg0yt]

I suggest to do the v2 update first.

For v3, there is #44699. It had to be draft due to microsoft/mimalloc#1166. It is closed now, but upstream didn't yet answer my question about the impact on android.