[ofw] rsocket.c & gtod.c duplicate include error.

[Hefty, Sean]

> Can it be that you were still using the "original" gtod.c? Because in my recent
> rsocket patch there was also contained an updated gtod.c with (among other
> things) gettimeofday() changed to static.
> However, non-static gettimeofday() is just as well for me. But I recommend to
> at least adopt my real modification of gtod.c, in order to fix a potential
> division-by-zero issue when calling gettimeofday() from a multi-threaded
> process (see also ofw Digest, Vol 68, Issue 2 from Dec 17, 2012).

I applied the original patch to the tree, did test builds, and committed those changes with only slight modifications to fix my build.  Stan pulled them, so he should have everything.