iwlwifi: mvm: small cleanups in quota management code

Use a C99 initializer to clear the command and move the lockdep
assertion before the restart check. Since this causes problems
with the BUILD_BUG_ON() with some compilers, change that a bit.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
diff --git a/drivers/net/wireless/iwlwifi/mvm/quota.c b/drivers/net/wireless/iwlwifi/mvm/quota.c
index 1897387..5c6ae16 100644
--- a/drivers/net/wireless/iwlwifi/mvm/quota.c
+++ b/drivers/net/wireless/iwlwifi/mvm/quota.c
@@ -131,7 +131,7 @@
 
 int iwl_mvm_update_quotas(struct iwl_mvm *mvm, struct ieee80211_vif *newvif)
 {
-	struct iwl_time_quota_cmd cmd;
+	struct iwl_time_quota_cmd cmd = {};
 	int i, idx, ret, num_active_macs, quota, quota_rem;
 	struct iwl_mvm_quota_iterator_data data = {
 		.n_interfaces = {},
@@ -139,15 +139,14 @@
 		.new_vif = newvif,
 	};
 
+	lockdep_assert_held(&mvm->mutex);
+
 	/* update all upon completion */
 	if (test_bit(IWL_MVM_STATUS_IN_HW_RESTART, &mvm->status))
 		return 0;
 
-	BUILD_BUG_ON(data.colors[MAX_BINDINGS - 1] != -1);
-
-	lockdep_assert_held(&mvm->mutex);
-
-	memset(&cmd, 0, sizeof(cmd));
+	/* iterator data above must match */
+	BUILD_BUG_ON(MAX_BINDINGS != 4);
 
 	ieee80211_iterate_active_interfaces_atomic(
 		mvm->hw, IEEE80211_IFACE_ITER_NORMAL,