Patch merged into coreboot/master: nb/intel/sandybridge/raminit: add additional fallbacks

the following patch was just integrated into master:
commit 2ccb74b6e97381ce2b2f8520076204f7737ade4c
Author: Patrick Rudolph 
Date:   Sat Mar 26 12:16:29 2016 +0100

nb/intel/sandybridge/raminit: add additional fallbacks

Add the following fallbacks:
    * Try decreasing clock frequency.
       In case of DDR1600 the next possible value of DDR1333 is being used.
    * Try decreasing clock frequency.
       In case of DDR1333 the next possible value of DDR1066 is being used.
    * Disable failing channel.
       The system may be able to boot with a single channel enabled.

The fallbacks are untested.

Change-Id: I3be7034ad25312b3ebf47a54f335a3893f8d7cc1
    Signed-off-by: Patrick Rudolph 
    Reviewed-on: https://review.coreboot.org/14173
    Tested-by: build bot (Jenkins)
    Reviewed-by: Martin Roth

See https://review.coreboot.org/14173 for details.

-gerrit