SDAG: Clean up dangling nodes in AArch64ISelDAGToDAG::SelectImpl

When we convert to the void Select interface, leaving unreferenced
nodes around won't be allowed anymore.

Part of llvm.org/pr26808.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@269345 91177308-0d34-0410-b5e6-96231b3b80d8
1 file changed