[SDAG] Fix a result chain in ExpandUnalignedLoad

On the code path in ExpandUnalignedLoad which expands an unaligned vector/fp
value in terms of a legal integer load of the same size, the ChainResult needs
to be the chain result of the integer load.

No in-tree test case is currently available.

Patch by Jan Hranac!

llvm-svn: 243956

llvm/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp

@@ -439,7 +439,7 @@ ExpandUnalignedLoad(LoadSDNode *LD, SelectionDAG &DAG,
                              ISD::ANY_EXTEND, dl, VT, Result);
 
       ValResult = Result;
-      ChainResult = Chain;
+      ChainResult = newLoad.getValue(1);
       return;
     }