On error flow resources being freed in esw_master_egress_destroy_resources()
but pointers not being set to null if error flow is from creating a
bounce rule. Then in esw_acl_egress_ofld_cleanup() we try to access already
freed pointers. Fix it by resetting the pointers to null.
Also if error is from creating a second or later bounce rule then the
flow group and table being used and cannot and should not be freed.
Add a check to destroy the flow group and table if there are no bounce
rules.