Add a driver for Arasan's SDHCI controller core.
Signed-off-by: NSoren Brinkmann <soren.brinkmann@xilinx.com>
Acked-by: Rob Herring <rob.herring@calxeda.com> [binding]
Acked-by: NMichal Simek <monstr@monstr.eu>
Signed-off-by: NChris Ball <chris@printf.net>