Bad performance on x64 branch with jit

[thegrb93]

Facepunch/garrysmod-issues#4100

[thegrb93]

A good work-around is to add jit.off() in lua/include/init.lua

[thegrb93]

Going to try this https://github.com/PAC3-Server/notagain/blob/master/lua/notagain/optimizations/preinit/luaify.lua#L6-L76