minor #12423 [Ldap] Add security LdapUser and provider (4.4) (hiddewie)

This PR was squashed before being merged into the 4.4 branch (closes #12423).

Discussion
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[Ldap] Add security LdapUser and provider (4.4)

#12088 and symfony/symfony#32824

![image](https://user-images.githubusercontent.com/1073881/66232348-ed53bd00-e6e8-11e9-9430-ccc5cc953c2f.png)

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a4ea784 [Ldap] Add security LdapUser and provider (4.4)

Author: javiereguiluz

security/ldap.rst

@@ -9,7 +9,7 @@ Symfony provides different means to work with an LDAP server.
 The Security component offers:
 
 * The ``ldap`` :doc:`user provider</security/user_provider>`, using the
-  :class:`Symfony\\Component\\Security\\Core\\User\\LdapUserProvider`
+  :class:`Symfony\\Component\\Ldap\\Security\\LdapUserProvider`
   class. Like all other user providers, it can be used with any
   authentication provider.
 
@@ -34,6 +34,12 @@ This means that the following scenarios will work:
 * Loading user information from an LDAP server, while using another
   authentication strategy (token-based pre-authentication, for example).
 
+.. deprecated:: 4.4
+
+    The class ``Symfony\Component\Security\Core\User\LdapUserProvider``
+    has been deprecated in Symfony 4.4. Use the class
+    ``Symfony\Component\Ldap\Security\LdapUserProvider`` instead.
+
 Installation
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