ARM: EXYNOS4: Rename sclk_cam clocks for FIMC driver

The sclk_cam clocks are now controlled by the top level FIMC media
device driver bound to "s5p-fimc-md" platform device.
Rename sclk_cam clocks so they accessible by the corresponding
driver.

Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>