Revert "[SelectionDAG] Extract [US]MULO expansion into TL method; NFC"

This reverts commit r353611.

Triggers an assertion during the libcall expansion on ARM.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@353612 91177308-0d34-0410-b5e6-96231b3b80d8
3 files changed