Revert change 335077 "[InlineSpiller] Fix a crash due to lack of forward...

Revert change 335077 "[InlineSpiller] Fix a crash due to lack of forward progress from remat specifically for STATEPOINT"
    
This change caused widespread assertion failures in our downstream testing:
lib/CodeGen/LiveInterval.cpp:409: bool llvm::LiveRange::overlapsFrom(const llvm::LiveRange&, llvm::LiveRange::const_iterator) const: Assertion `!empty() && "empty range"' failed.

llvm-svn: 335462