Prompt for recovery key on login rather than passphrase

Only show passphrase options at all if the user has a passphrase on
their SSSS key.

res/css/structures/auth/_CompleteSecurity.scss

@@ -70,6 +70,10 @@ limitations under the License.
     }
 }
 
+.mx_CompleteSecurity_recoveryKeyInput {
+    width: 368px;
+}
+
 .mx_CompleteSecurity_heroIcon {
     width: 128px;
     height: 128px;