[RFA] varobj.c: check wrapper return value

[Andrew Cagney]

> 
> Thanks.  Please check it in the trunk.
> 
> I can't tell about 5.1.  Andrew?

Really it is up to you and Keith.  What is its impact? If it is just MI 
and insight then it is very likely ok.

5.1 still has true64 and s390.  I think HP/UX 11 was resolved?

Andrew