[OE-core] configure error for glibc 2.25.2

[Andrew Goodbody]

> From: Richard Purdie [mailto:richard.purdie at linuxfoundation.org]
> Sorry, yes, you're totally right. I hadn't remembered there were two
> places we were making this assumption! That does look like the right
> fix although I might rework that code slightly.

Feel free. I'm off to fix all the other fallout in my recipes from recipe specific sysroots.

Andrew