[patch] keyctl.2: declare auth_key

[Oleksandr Kravchuk <open.source@xxxxxxxxxxxxxxxxxxxxxx>]

The variable is used in the code example, but not declared, leading to
an expected compilation error:

    `error: ‘auth_key’ undeclared (first use in this function)`.

Signed-off-by: Oleksandr Kravchuk <open.source@xxxxxxxxxxxxxxxxxxxxxx>
---
 man2/keyctl.2 | 1 +
 1 file changed, 1 insertion(+)

diff --git a/man2/keyctl.2 b/man2/keyctl.2
index 3dea4266c..08ae92d6d 100644
--- a/man2/keyctl.2
+++ b/man2/keyctl.2
@@ -2103,6 +2103,7 @@ main(int argc, char *argv[])
     char dbuf[256];
     char auth_key_payload[256];
     int akp_size;       /* Size of auth_key_payload */
+    int auth_key;
 
     fp = fopen("/tmp/key_instantiate.log", "w");
     if (fp == NULL)
-- 
2.17.1