[WebAssembly] Revert r319186 "Support bitcasted function addresses with varargs."

The patch broke Emscripten's EM_ASM macros, which utiltize unprototyped
functions.

See https://bugs.llvm.org/show_bug.cgi?id=35385 for details.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@319452 91177308-0d34-0410-b5e6-96231b3b80d8
4 files changed