ARM: EXYNOS: make exynos_core_restart() less verbose

There is a kernel message about secondary CPU bootup when
exynos_core_restart() is called through CPU hotplug code-path (the
only exynos_core_restart() user currently) so there is no need for
an extra info on Exynos3250 SoC about software reset.  This also
prepares exynos_core_restart() to be re-used in coupled cpuidle
code-path in the future.

Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: Kukjin Kim <kgene@kernel.org>