clk: exynos4: Use SRC_MASK_PERIL{0,1} definitions

There are definitions of SRC_MASK_PERIL0 and SRC_MASK_PERIL1 registers,
but they are not used for clock definitions. This patch modifies related
clock definitions to use defined macros instead of numeric offsets.

Signed-off-by: Tomasz Figa <t.figa@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Reviewed-by: Thomas Abraham <thomas.abraham@linaro.org>
Acked-by: Mike Turquette <mturquette@linaro.org>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>