Revert "[SCCP] Constant propagation through freeze instruction"

This reverts commit 559d47a1.

Caused failure on sanitizer-aarch64-linux-bootstrap-ubsan:

    clang++: /b/sanitizer-aarch64-linux-bootstrap-ubsan/build/llvm-project/llvm/lib/Transforms/Utils/SCCPSolver.cpp:442: llvm::ValueLatticeElement &llvm::SCCPInstVisitor::getValueState(llvm::Value *): Assertion `!V->getType()->isStructTy() && "Should use getStructValueState"' failed.