configs: Migrate CONFIG_USB_STORAGE

In some cases we were missing CONFIG_USB=y so enable that when needed.

Reviewed-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Tom Rini <trini@konsulko.com>
diff --git a/configs/at91sam9261ek_nandflash_defconfig b/configs/at91sam9261ek_nandflash_defconfig
index 45bc427..c985d3a 100644
--- a/configs/at91sam9261ek_nandflash_defconfig
+++ b/configs/at91sam9261ek_nandflash_defconfig
@@ -15,4 +15,6 @@
 CONFIG_CMD_DHCP=y
 CONFIG_CMD_PING=y
 CONFIG_CMD_FAT=y
+CONFIG_USB=y
+CONFIG_USB_STORAGE=y
 CONFIG_OF_LIBFDT=y