Fix bug in Subzero bitcode reader for insertelement instruction.

Instruction insertelement was incorrectly generating a result
corresponding to the element type, instead of the updated
vector type.

BUG= None
R=jvoung@chromium.org

Review URL: https://codereview.chromium.org/604023003
diff --git a/src/PNaClTranslator.cpp b/src/PNaClTranslator.cpp
index 35108cc..6c0ee8a 100644
--- a/src/PNaClTranslator.cpp
+++ b/src/PNaClTranslator.cpp
@@ -1608,7 +1608,7 @@
     // TODO(kschimpf): Restrict index to a legal constant index (once
     // constants can be defined).
     CurrentNode->appendInst(Ice::InstInsertElement::create(
-        Func, getNextInstVar(EltType), Vec, Elt, Index));
+        Func, getNextInstVar(VecType), Vec, Elt, Index));
     break;
   }
   case naclbitc::FUNC_CODE_INST_CMP2: {