clk: exynos4: Remove remnants of non-DT support

This patch simplifies a bit clock initialization code by removing
remnants of non-DT clock initialization, such as reg_base and xom values
passed in function parameters.

Signed-off-by: Tomasz Figa <t.figa@samsung.com>
Acked-by: Kyungmin Park <kyungmin.park@samsung.com>
Reviewed-by: Thomas Abraham <thomas.ab@samsung.com>
Reviewed-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>