Remove unused struct member in ssl_context

Actually belongs to ssl_session
diff --git a/include/mbedtls/ssl.h b/include/mbedtls/ssl.h
index d6a686d..cc9a198 100644
--- a/include/mbedtls/ssl.h
+++ b/include/mbedtls/ssl.h
@@ -749,7 +749,6 @@
      * PKI layer
      */
     int client_auth;                    /*!<  flag for client auth.   */
-    int verify_result;                  /*!<  verification result     */
 
     /*
      * User settings