PM / devfreq: exynos-nocp: Remove redundant code

load_count/total_count are reset by devfreq_event_get_event(), so
remove the redundant code in exynos_nocp_get_event().

Signed-off-by: Axel Lin <axel.lin@ingics.com>
Acked-by: Chanwoo Choi <cw00.choi@samsung.com>
[ rjw: Subject/changelog ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>