Revert "CodeGen: ensure placeholder instruction for cleanup is created"

Originally in https://reviews.llvm.org/D64656

Causes bot failures:

/home/buildslave/buildslave/clang-cmake-armv8-full/llvm/tools/clang/test/CodeGenCXX/pr40771-ctad-with-lambda-copy-capture.cpp:20:16: error: CHECK-NEXT: expected string not found in input
// CHECK-NEXT: call void @_ZN1RC1E1Q(%struct.R* [[TMP_R]])
               ^
<stdin>:37:2: note: scanning from here
 %8 = call %struct.R* @_ZN1RC1E1Q(%struct.R* %1)
 ^
<stdin>:37:2: note: with "TMP_R" equal to "%1"
 %8 = call %struct.R* @_ZN1RC1E1Q(%struct.R* %1)
 ^
<stdin>:37:17: note: possible intended match here
 %8 = call %struct.R* @_ZN1RC1E1Q(%struct.R* %1)
                ^

llvm-svn: 367051