[gnome-applets] build: remove unused LIBPANEL_REQUIRED

[Alberts Muktupāvels <muktupavels src gnome org>]

commit 12eb73927997625568827ac6d475b76a98631277
Author: Dmitry Shachnev <mitya57 gmail com>
Date:   Thu May 28 12:43:49 2020 +0300

    build: remove unused LIBPANEL_REQUIRED

 configure.ac | 1 -
 1 file changed, 1 deletion(-)
---
diff --git a/configure.ac b/configure.ac
index c8009d332..a327c65a1 100644
--- a/configure.ac
+++ b/configure.ac
@@ -68,7 +68,6 @@ dnl ***************************************************************************
 GTK_REQUIRED=3.20.0
 GLIB_REQUIRED=2.44.0
 GIO_REQUIRED=2.26.0
-LIBPANEL_REQUIRED=3.24.1
 LIBGNOME_PANEL_REQUIRED=3.37.0
 LIBGTOP_REQUIRED=2.11.92
 LIBWNCK_REQUIRED=3.14.1