Update logic to detect DVR in rescheduling test

The previous logic to determine of DVR was enabled
was based on checking a config variable that would
always return False.

This patch corrects it by checking for the distributed
flag on the router using the admin credentials.

Closes-Bug: #1489929
Change-Id: I47ee7bdfeb5aa3583c56e336de5a683bb1f48cf7
1 file changed