Patch merged into coreboot/master: 53abac1 amd/cimx/rd890/amd.h: Eliminate redefinition of NULL

the following patch was just integrated into master:
commit 53abac1767c5c40ce0eafe729cd04cca1fcc8292
Author: Bruce Griffith 
Date:   Tue Jun 25 14:27:16 2013 -0600

amd/cimx/rd890/amd.h: Eliminate redefinition of NULL

This change replaces a redefinition of NULL with the standard
    definition from <stddef.h> to eliminate a compiler redefinition
    warning.

Change-Id: I441fa569f545c0efb00284b5ee58aa27cb6617ba
    Signed-off-by: Bruce Griffith 
    Reviewed-on: http://review.coreboot.org/3540
    Reviewed-by: Paul Menzel 
    Tested-by: build bot (Jenkins)
    Reviewed-by: Stefan Reinauer

See http://review.coreboot.org/3540 for details.

-gerrit