mmc: sdhci-s3c: use mmc_of_parse and remove the card_tasklet

Fix the compile error.
(Removed the card_tasklet at "mmc: sdhci: push card_tasklet into treaded irq handler")

drivers/mmc/host/sdhci-s3c.c: In function ‘sdhci_s3c_notify_change’:
drivers/mmc/host/sdhci-s3c.c:402:25: error: ‘struct sdhci_host’ has no member named ‘card_tasklet’

Signed-off-by: Jaehoon Chung <jh80.chung@samsung.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Chris Ball <chris@printf.net>