clockevents/drivers/exynos_mct: Remove unneeded container_of()

Patch removes unneeded container_of() macro in exynos4_local_timer_setup().
Instead let's pass mevt pointer to setup and stop functions from
exynos4_mct_cpu_notify() and let them get evt pointer.

Tested on odroid-xu3.

Signed-off-by: Alexey Klimov <klimov.linux@gmail.com>
Acked-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Reviewed-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>