ARM: S5PC100: cleanup hsmmc clock definitions

This patch performs minor clocks cleanup for S5PC100 SoC. HSMMC special
clocks has been renamed back to sclk_mmc to match the common style of
clock names. This clock has been also added to sdhci clock source list.
The duplicate HCLK clock entry for sdhci-s3c has been disabled.

Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>