Added a new function: ep93xx_chip_revision() which reads chip revision
from the sysconfig register.
Signed-off-by: NMika Westerberg <mika.westerberg@iki.fi>
Acked-by: NH Hartley Sweeten <hsweeten@visionengravers.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>