clk: samsung: exynos4: add cpu clock configuration data and instantiate cpu clock

With the addition of the new Samsung specific cpu-clock type, the
arm clock can be represented as a cpu-clock type. Add the CPU clock
configuration data and instantiate the CPU clock type for Exynos4210.

Changes by Bartlomiej:
- fixed issue with wrong dividers being setup by Common Clock Framework
  (by an addition of CLK_RECALC_NEW_RATES clock flag to mout_apll clock,
  without this change cpufreq-dt driver showed ~10 mA larger energy
  consumption when compared to cpufreq-exynos one when "performance"
  cpufreq governor was used on Exynos4210 SoC based Origen board), this
  was probably meant to be workarounded by use of CLK_GET_RATE_NOCACHE
  and CLK_DIVIDER_READ_ONLY clock flags in the original patchset (in
  "[PATCH v12 6/6] clk: samsung: remove unused clock aliases and update
  clock flags") but using these flags is not sufficient to fix the issue
  observed
- removed Exynos5250 and Exynos5420 support for now

Cc: Tomasz Figa <tomasz.figa@gmail.com>
Cc: Mike Turquette <mturquette@linaro.org>
Cc: Javier Martinez Canillas <javier.martinez@collabora.co.uk>
Signed-off-by: Thomas Abraham <thomas.ab@samsung.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: Michael Turquette <mturquette@baylibre.com>