Revert "Cleanup floatingips also on router delete"

This reverts commit c3326996e38cb67f8d4ba3dabd829dc6f327b666.

The patch being reverted here addresses an issue that can no longer be
reproduced, in that under no circumstances, I can make the FIP lie around
before deleting a router (which can only be done after all FIP have been
disassociated or released).

Unless we have more clarity as to what the initial commit was really meant
to fix, there is a strong case for reverting this patch at this point.

Closes-bug: #1373100

Change-Id: I7e0f80e456ff4d9eb57a1d31c6ffc7cdfca5a163
Merge "Revert "Cleanup floatingips also on router delete""