Merge pull request #921 from jaredchesebro/7.dev

Update system-configuration-overrides.md (Add enable_mfa)

docs/general/system-configuration-overrides.md

@@ -1298,8 +1298,23 @@ Example Usage:
 
 **Also found in CP:** `Settings --> Tracking`: [Enable Template Hit Tracking](control-panel/settings/hit-tracking.md#enable-template-hit-tracking)
 
+
+## `enable_mfa`
+
+If enabled, the Multi-factor authentication (MFA) options will become available for member roles.
+
+| Value | Behavior                               |
+| ----- | -------------------------------------- |
+| y     | Enable Multi-factor authentication |
+| n     | Disable Multi-factor authentication (default) |
+
+Example Usage:
+
+    $config['enable_mfa'] = 'y';
+
 ## `enable_online_user_tracking`
 
+
 If enabled, online user statistics are tracked and the user-based variables in the [Statistics](add-ons/statistics.md) module are available for use.
 
 | Value | Behavior                               |