Handle error case when yylex() failed to parse.

Remove the incorrect characters in rs.spec as well.

Change-Id: I7106e263e79239b970a7a1442efe2625dbe28298
diff --git a/rs.spec b/rs.spec
index c2e3fd8..e9051ac 100644
--- a/rs.spec
+++ b/rs.spec
@@ -159,7 +159,7 @@
     param uint32_t z
     param uint32_t array
     param size_t *stride
-    ret void *s
+    ret void *
     }
 
 Allocation1DData {
@@ -367,7 +367,7 @@
 ScriptInvokeIDCreate {
     param RsScript s
     param uint32_t slot
-    ret RsScriptInvokeID;
+    ret RsScriptInvokeID
     }
 
 ScriptInvoke {