macros: Rename generate_element_with_only_attributes!() into generate_element!().

src/eme.rs

@@ -4,9 +4,10 @@
 // License, v. 2.0. If a copy of the MPL was not distributed with this
 // file, You can obtain one at http://mozilla.org/MPL/2.0/.
 
-generate_element_with_only_attributes!(
+generate_element!(
 /// Structure representing an `<encryption xmlns='urn:xmpp:eme:0'/>` element.
-ExplicitMessageEncryption, "encryption", EME, [
+ExplicitMessageEncryption, "encryption", EME,
+attributes: [
     /// Namespace of the encryption scheme used.
     namespace: String = "namespace" => required,