Patch merged into coreboot/master: 23aad4a lenovo/t520: fix usb config & documentation

the following patch was just integrated into master:
commit 23aad4a83c3390dc39f7d1c1f5422f7ac54a80f3
Author: Nicolas Reinecke 
Date:   Sat Aug 23 00:51:49 2014 +0200

lenovo/t520: fix usb config & documentation

Change-Id: I71398ab2d7ef5b9256795861dd2bebbb0cf32d5f
    Signed-off-by: Nicolas Reinecke 
    Reviewed-on: http://review.coreboot.org/6742
    Tested-by: build bot (Jenkins)
    Reviewed-by: Edward O'Callaghan 
    Reviewed-by: Paul Menzel

See http://review.coreboot.org/6742 for details.

-gerrit