clk: exynos3250: Add cpu clock configuration data and instaniate cpu clock

This patch add CPU clock configuration data and instantiate the CPU
clock type for Exynos3250 to support Samsung specific cpu-clock type.

Cc: Sylwester Nawrocki <s.nawrocki@samsung.com>
Cc: Tomasz Figa <tomasz.figa@gmail.com>
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
Acked-by: Kyungmin Park <kyungmin.park@samsung.com>
Reviewed-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Reviewed-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Acked-by: Michael Turquette <mturquette@baylibre.com>
Signed-off-by: Kukjin Kim <kgene@kernel.org>