ARM: S5P64X0: Fix typo "CONFIG_S5P64X0_SETUP_SDHCI"

Commit ebc433c2 ("ARM: S5P64X0: Add HSMMC setup for host
Controller") added the Kconfig symbol S5P64X0_SETUP_SDHCI_GPIO.
By accident it also used a macro CONFIG_S5P64X0_SETUP_SDHCI.
Fix that typo.

Signed-off-by: Paul Bolle <pebolle@tiscali.nl>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>