Patch merged into filo/master: baf1339 makefile: build system cleanup

the following patch was just integrated into master:
commit baf1339a1334616c73cbbf9cd7743d54b4a86ff3
Author: Mathias Krause 
Date:   Tue Mar 6 13:37:05 2012 +0100

makefile: build system cleanup

This patch cleans up the include hierarchies for the Makefile system to
    decrease the knowledge of the main Makefile about every subdirectory.
    This allows us to add new drivers without the need to patch the main
    Makefile but, instead, just add a line to the appropriate Makefile.inc.

Also all standard make variables are cleaned up (e.g. CFLAGS,
    CPPFLAGS,..). This, in turn, allows modifying them as needed in the
    included Makefile.inc to add flags or even library dependencies.

It's no Linux Kbuild yet, but we're close ;)

Change-Id: I67be4fcdd07d6960a7e46bfb6a3c0ea41f280e2b
    Signed-off-by: Mathias Krause

Build-Tested: build bot (Jenkins) at Wed Mar  7 16:45:22 2012, giving +1
Reviewed-By: Stefan Reinauer  at Wed Mar  7 17:45:09 2012, giving +2
See http://review.coreboot.org/746 for details.

-gerrit