fix build breakage in eeh.c in 2.6.16-rc5-git5

[Paul Mackerras]

Greg KH writes:

> This patch should fixe a problem with eeh_add_device_late() not being
> defined in the ppc64 build process, causing the build to break.

John Rose just sent a patch making eeh_add_device_late static and
moving it to be defined before it is called in
arch/powerpc/platforms/pseries/eeh.c.

Since he maintains this stuff, I'm more inclined to take his patch.

Paul.