Patch merged into coreboot/master: arch/x86: document CAR symbols and expose them in symbols.h

the following patch was just integrated into master:
commit dd56de974ddc7d0d8d782b50d9260b0596f59a1a
Author: Andrey Petrov 
Date:   Thu Feb 25 17:22:17 2016 -0800

arch/x86: document CAR symbols and expose them in symbols.h

Attempt to better document the symbol usage in car.ld for
    cache-as-ram usage. Additionally, add _car_region_[start|end]
    that completely covers the entire cache-as-ram region. The
    _car_data_[start|end] symbols were renamed to
    _car_relocatable_data_[start|end] in the hopes of making it
    clearer that objects within there move. Lastly, all these
    symbols were added to arch/symbols.h.

Change-Id: I1f1af4983804dc8521d0427f43381bde6d23a060
    Signed-off-by: Andrey Petrov 
    Signed-off-by: Aaron Durbin 
    Reviewed-on: https://review.coreboot.org/13804
    Tested-by: build bot (Jenkins)
    Reviewed-by: Martin Roth 
    Reviewed-by: Furquan Shaikh

See https://review.coreboot.org/13804 for details.

-gerrit