Add support for architecture specific EDAC atomic_scrub to ARM. Only ARMv6+
is implemented as ldrex/strex instructions are needed. Supporting EDAC on
ARMv5 or earlier is unlikely at this point anyway.
Signed-off-by: NRob Herring <rob.herring@calxeda.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>