simplify tempRet0 logic - always import them from JS

lib/Target/JSBackend/CallHandlers.h

diff --git a/lib/Target/JSBackend/CallHandlers.h b/lib/Target/JSBackend/CallHandlers.h
index 6927c04..66dfd1a 100644
--- a/lib/Target/JSBackend/CallHandlers.h
+++ b/lib/Target/JSBackend/CallHandlers.h
@@ -203,11 +203,11 @@
 })
 
 std::string getTempRet0() {
-  return Relocatable ? "(getTempRet0() | 0)" : "tempRet0";
+  return "(getTempRet0() | 0)";
 }
 
 std::string setTempRet0(std::string Value) {
-  return Relocatable ? "setTempRet0((" + Value + ") | 0)" : "tempRet0 = (" + Value + ')';
+  return "setTempRet0((" + Value + ") | 0)";
 }
 
 // setjmp support