Add Qemu TCG to JIT comparision in README

[cyrilmhansen]

Qemu includes its own JIT and interpreter subsystems.

Maybe it can be useful to describe mir design difference from it in JIT comparison section.

https://wiki.qemu.org/Documentation/TCG
https://wiki.qemu.org/Features/TCI

[vnmakarov]

Thank you for the links. I was not aware of that Qemu has a JIT. I was interesting in JIT technology for Valgrind but had no time to learn it more.

They are now interesting to me because they are part of widely used applications unlike many practically not used JIT engines and libraries. Mine is still in the second category and I need to start to work on MIR real usage to move it in the 1st category. I think MIR will be ready for starting this work only in the summer.

I will try to find time to learn Qemu and Valgrind JITs more. After that I can update the comparison section.

Thank you again.