Fix "no-ui" configuration

Reviewed-by: Matt Caswell <matt@openssl.org>
diff --git a/apps/apps.c b/apps/apps.c
index e124149..7ba12fe 100644
--- a/apps/apps.c
+++ b/apps/apps.c
@@ -266,6 +266,7 @@
     return 0;
 }
 
+#ifndef OPENSSL_NO_UI
 static int ui_open(UI *ui)
 {
     return UI_method_get_opener(UI_OpenSSL())(ui);
@@ -335,20 +336,25 @@
         ui_method = NULL;
     }
 }
+#endif
 
 int password_callback(char *buf, int bufsiz, int verify, PW_CB_DATA *cb_tmp)
 {
-    UI *ui = NULL;
     int res = 0;
+#ifndef OPENSSL_NO_UI
+    UI *ui = NULL;
     const char *prompt_info = NULL;
+#endif
     const char *password = NULL;
     PW_CB_DATA *cb_data = (PW_CB_DATA *)cb_tmp;
 
     if (cb_data) {
         if (cb_data->password)
             password = cb_data->password;
+#ifndef OPENSSL_NO_UI
         if (cb_data->prompt_info)
             prompt_info = cb_data->prompt_info;
+#endif
     }
 
     if (password) {
@@ -359,6 +365,7 @@
         return res;
     }
 
+#ifndef OPENSSL_NO_UI
     ui = UI_new_method(ui_method);
     if (ui) {
         int ok = 0;
@@ -408,6 +415,7 @@
         UI_free(ui);
         OPENSSL_free(prompt);
     }
+#endif
     return res;
 }