[Buildroot] Patch for busybox config file name

For revision 18994 I needed this patch:

--- buildroot/package/busybox/Config.in 2007-07-02 23:59:49.000000000 +0700
+++ buildroot.new/package/busybox/Config.in     2007-07-02

23:51:10.000000000 +0700

@@ -100,6 +100,7 @@
        default "package/busybox/busybox-1.5.0.config" if

BR2_BUSYBOX_VERSION_1_5_0
        default "package/busybox/busybox-1.5.0.config" if
BR2_BUSYBOX_VERSION_1_5_1
        default "package/busybox/busybox-1.6.0.config" if
BR2_BUSYBOX_VERSION_1_6_0
+       default "package/busybox/busybox-1.6.1.config" if
BR2_BUSYBOX_VERSION_1_6_1
        help
          Some people may wish to use their own modified BusyBox configuration
          file, and will specify their config file location with this option.