lrdp_V2 : Fix for broken ion_buffer_parse.py

in some case db_list is corrupted so parsing the db_list in
both forward and reverse direction to get more ion buffer usages
data.

Change-Id: Ic48aa737b0939d83517d501700577b7a27e85188
Signed-off-by: Ankur Bansal <ankban@codeaurora.org>