[CA-147162] Don't rethrow failures to delete root#xenevtchn

Signed-off-by: Ben Chalmers <Ben.Chalmers@citrix.com>
Merge pull request #97 from benchalmers/ccatch

[CA-147162] Don't rethrow failures to delete root#xenevtchn

Approved-By: Ben.Chalmers@citrix.com