iwlwifi: mvm: add the quota remainder to a data binding

Currently the quota remainder was added to the first binding, although
it is possible that this was not a data binding (only the P2P_DEVICE
interface is part of the binding).

Fix this by adding the remainder to the first binding that was actually
allocated quota.

Signed-off-by: Ilan Peer <ilan.peer@intel.com>
Reviewed-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>