VT: Add interarrival jitter time to RR

Replace the interarrival time in RR
from void 0 value to calculated one.

Bug: 201473503
Test: Manually MMQoE test

Signed-off-by: Kim Sungyeon <sy85.kim@samsung.com>
Change-Id: I683697d28f180d7622a4771b3afd37a8d94eccd4