kernel: timeslicing: add time slice reset in slice per thread api

This will reset time slice in k_thread_time_slice_set()
when slice per thread api is used.

Currently it will reset it only in standard slice_set

Signed-off-by: Adrian Bonislawski <adrian.bonislawski@intel.com>

kernel/timeslicing.c

diff --git a/kernel/timeslicing.c b/kernel/timeslicing.c
index 401bcea..07ae497 100644
--- a/kernel/timeslicing.c
+++ b/kernel/timeslicing.c
@@ -95,6 +95,7 @@
 		thread->base.slice_ticks = thread_slice_ticks;
 		thread->base.slice_expired = expired;
 		thread->base.slice_data = data;
+		z_reset_time_slice(thread);
 	}
 }
 #endif