[contract] fix error messages on multicall code

contract/vm.go

@@ -1386,7 +1386,11 @@ func vmAutoload(L *LState, funcName string) bool {
 func (ce *executor) vmLoadCode(id []byte) {
 	var chunkId *C.char
 	if HardforkConfig.IsV3Fork(ce.ctx.blockInfo.No) {
-		chunkId = C.CString("@" + types.EncodeAddress(id))
+		if ce.ctx.isMultiCall {
+			chunkId = C.CString("@multicall")
+		} else {
+			chunkId = C.CString("@" + types.EncodeAddress(id))
+		}
 	} else {
 		chunkId = C.CString(hex.EncodeToString(id))
 	}