pcmcia: at91_cf: Use syscon to configure the MC/smc

Use syscon/regmap to configure the smc part of the memory controller. This
allows to avoid using mach/at91rm9200_mc.h and mach/at91_ramc.h and to compile
the driver in a multiplatform configuration.

Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>