clk: exynos5250: Fix parent clock for sclk_mmc{0,1,2,3}

commit 688f7d8c

 ("clk: exynos5250: Fix divider values for
sclk_mmc{0,1,2,3}") incorrectly sets the divider for sclk_mmc{0,1,2,3}
to fix the wrong clock value. Though this fixed issue with Arndale,
it created regressions for other boards like Snow.

On Exynos5250, sclk_mmc<n> is generated like below (as per the clock
names in drivers/clk/samsung/clk-exynos5250.c)

mout_group1_p ==> mout_mmc<n> ==>
		div_mmc<n> ==> div_mmc_pre<n> => sclk_mmc<n>

Earlier div_mmc<n> was set as the parent for sclk_mmc<n>, hence
div_mmc_pre<n> was not getting referred in kernel code and depending
on its value set during preboot, sclk_mmc<n> value was different for
various boards.

Setting the correct clock generation path should fix the issues
reported in above referenced commit. The changes committed during the
earlier patch has also been reverted here.

Reported-by: Doug Anderson <dianders@chromium.org>
Signed-off-by: Tushar Behera <tushar.behera@linaro.org>
Tested-by: Doug Anderson <dianders@chromium.org>
Acked-by: Kukjin Kim <kgene.kim@samsung.com>
Signed-off-by: Olof Johansson <olof@lixom.net>