mmc: sdhci-of-arasan: Add the support for sdhci-arasan4.9a

This patch adds the quirks and compatible string in sdhci-of-arasan.c
to support sdhci-arasan4.9a version of controller.

Signed-off-by: Suman Tripathi <stripathi@apm.com>
Reviewed-by: Michal Simek <michal.simek@xilinx.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>