configs: Enable progress meter for TFTP

This enables Petitboot after v1.4.0 to do fancy UI things with Busybox
utilities.

Signed-off-by: Samuel Mendoza-Jonas <sam@mendozajonas.com>
diff --git a/openpower/configs/witherspoon_defconfig b/openpower/configs/witherspoon_defconfig
index 098b377..56e16d9 100644
--- a/openpower/configs/witherspoon_defconfig
+++ b/openpower/configs/witherspoon_defconfig
@@ -20,6 +20,7 @@
 BR2_LINUX_KERNEL_CUSTOM_CONFIG_FILE="$(BR2_EXTERNAL)/configs/linux/skiroot_defconfig"
 BR2_LINUX_KERNEL_ZIMAGE_EPAPR=y
 BR2_LINUX_KERNEL_XZ=y
+BR2_PACKAGE_BUSYBOX_CONFIG_FRAGMENT_FILES="$(BR2_EXTERNAL)/configs/busybox.fragment"
 BR2_PACKAGE_BUSYBOX_SHOW_OTHERS=y
 BR2_PACKAGE_LINUX_FIRMWARE=y
 BR2_PACKAGE_LINUX_FIRMWARE_BNX2X=y