VT: Traffic recorder renewal

1. Switch head & tail definition to prevent confusing

HeadIdx_(n+1) = (HeadIdx_(n) + 1) mod Sizeof(RingBuffer)

X = filled index
O = vacant index
                                           head
          O O O X head                 O O X X
        O         X                  O         X
       O           X     write      O           X
       O           X     ----->     O           X
        O         X                  O         X
          O X X X                      O X X X
        tail                          tail

2. Preserve data when print information.
   The recorder keeps data as possible as it can.
   (Current recorder keeps data for 2000ms)

3. Limit traffic recorder size between 4 and 1024 entries.

Bug: 171688417

Change-Id: I7502f09f31d841b04a5d29efb7bb1b904059b3c7
Signed-off-by: Kim Sungyeon <sy85.kim@samsung.com>