arm: kirkwood: enable DM_USB for LaCie board

This patch enables DM_USB and USB_STORAGE for the following
Kirkwood-based LaCie boards:

- d2 Network v2
- Internet Space v2
- 2Big Network v2
- Network Space v2
- Network Space Lite v2
- Network Space Max v2

Signed-off-by: Simon Guinot <simon.guinot@sequanux.org>
Reviewed-by: Stefan Roese <sr@denx.de>
diff --git a/configs/net2big_v2_defconfig b/configs/net2big_v2_defconfig
index e7b7be7..4d0e50b 100644
--- a/configs/net2big_v2_defconfig
+++ b/configs/net2big_v2_defconfig
@@ -52,4 +52,6 @@
 CONFIG_DM_SPI=y
 CONFIG_KIRKWOOD_SPI=y
 CONFIG_USB=y
+CONFIG_DM_USB=y
 CONFIG_USB_EHCI_HCD=y
+CONFIG_USB_STORAGE=y