[feature] Add support for gcc thread model 'mcf' for MINGW

[ErikTempelaarVO]

What is your suggestion?

Hi! I would like for conan to be able to support the mcfgthread model for gcc on Windows natively.

mcf is a new thread model, available in gcc since 13.1. gcc has it as --enable-thread option, it's called 'mcf'

See the thread line below:

        version: ["4.1", "4.4", "4.5", "4.6", "4.7", "4.8", "4.9",
                  "5", "5.1", "5.2", "5.3", "5.4", "5.5",
                  "6", "6.1", "6.2", "6.3", "6.4", "6.5",
                  "7", "7.1", "7.2", "7.3", "7.4", "7.5",
                  "8", "8.1", "8.2", "8.3", "8.4", "8.5",
                  "9", "9.1", "9.2", "9.3", "9.4", "9.5",
                  "10", "10.1", "10.2", "10.3", "10.4", "10.5",
                  "11", "11.1", "11.2", "11.3", "11.4",
                  "12", "12.1", "12.2", "12.3",
                  "13", "13.1", "13.2", "14"]
        libcxx: [libstdc++, libstdc++11]
        threads: [None, posix, win32, mcf]  # Windows MinGW

This way I can add it to my profiles

compiler.threads=mcf

Without having to install a custom setting.yaml to developer laptops or CI machines.

Thanks for taking this in consideration!

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