Remove dead code in MCC tests that causes compilation failure on NativeAOT win-x86 (#99719)

CoreCLR doesn't try to JIT the code and thus doesn't hit it:
https://github.com/dotnet/runtime/blob/d36beb7b0a3936d18062ca89572d49590fdd445a/src/coreclr/jit/lclvars.cpp#L458-L465

Author: filipnavara