iwlwifi: mvm: don't NUL-terminate low-latency debugfs file

There's obviously no reason to write a NUL-terminating byte into
the debugfs file. Apparently nobody tried to use this from a tool
that doesn't strip NUL bytes though, so we never noticed. Fix it.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Luciano Coelho <luciano.coelho@intel.com>

drivers/net/wireless/iwlwifi/mvm/debugfs-vif.c

@@ -1250,11 +1250,10 @@ static ssize_t iwl_dbgfs_low_latency_read(struct file *file,
 {
 	struct ieee80211_vif *vif = file->private_data;
 	struct iwl_mvm_vif *mvmvif = iwl_mvm_vif_from_mac80211(vif);
-	char buf[3];
+	char buf[2];
 
 	buf[0] = mvmvif->low_latency ? '1' : '0';
 	buf[1] = '\n';
-	buf[2] = '\0';
 	return simple_read_from_buffer(user_buf, count, ppos, buf, sizeof(buf));
 }