iwlwifi: mvm: don't update quota in firmware too often

When updating quota in the firmware, it has to reset quite a bit
of internal state, which apparently can have an adverse impact on
its operation.

Avoid that by only updating the quota command when there are any
signification changes, i.e. added/removed bindings or changes in
quota that are bigger than 8 TU within a binding.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>