7091290: fails to build jdk8 b05 Embedded build

Reviewed-by: xuelei, dholmes

src/share/classes/org/ietf/jgss/Oid.java

@@ -157,7 +157,7 @@ public class Oid {
             return (true);
 
         if (other instanceof Oid)
-            return this.oid.equals(((Oid) other).oid);
+            return this.oid.equals((Object)((Oid) other).oid);
         else if (other instanceof ObjectIdentifier)
             return this.oid.equals(other);
         else