[libgit2-glib] ggit-cred-ssh-key-from-agent.c: Fix return annotations

[Igor Gnatenko <ignatenko src gnome org>]

commit f3b903ec5915fee7568e35442970f014eff20053
Author: Brian C. Lane <bcl redhat com>
Date:   Wed Aug 30 16:04:27 2017 -0700

    ggit-cred-ssh-key-from-agent.c: Fix return annotations
    
    Add (nullable) as needed.

 libgit2-glib/ggit-cred-ssh-key-from-agent.c |    4 ++--
 1 files changed, 2 insertions(+), 2 deletions(-)
---
diff --git a/libgit2-glib/ggit-cred-ssh-key-from-agent.c b/libgit2-glib/ggit-cred-ssh-key-from-agent.c
index 14c1f4b..2931b43 100644
--- a/libgit2-glib/ggit-cred-ssh-key-from-agent.c
+++ b/libgit2-glib/ggit-cred-ssh-key-from-agent.c
@@ -173,7 +173,7 @@ ggit_cred_ssh_key_from_agent_initable_iface_init (GInitableIface *iface)
  *
  * Creates a new #GgitCredSshKeyFromAgent.
  *
- * Returns: (transfer full): a new #GgitCredSshKeyFromAgent or %NULL if there was an error.
+ * Returns: (transfer full) (nullable): a new #GgitCredSshKeyFromAgent or %NULL if there was an error.
  */
 GgitCredSshKeyFromAgent *
 ggit_cred_ssh_key_from_agent_new (const gchar  *username,
@@ -191,7 +191,7 @@ ggit_cred_ssh_key_from_agent_new (const gchar  *username,
  *
  * Gets the username for the credential.
  *
- * Returns: the username.
+ * Returns: (transfer none) (nullable): the username or %NULL.
  */
 const gchar *
 ggit_cred_ssh_key_from_agent_get_username (GgitCredSshKeyFromAgent *cred)