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/trimslice_defconfig b/configs/trimslice_defconfig
index 5530b23..201a870 100644
--- a/configs/trimslice_defconfig
+++ b/configs/trimslice_defconfig
@@ -36,3 +36,4 @@
 CONFIG_TEGRA20_SFLASH=y
 CONFIG_USB=y
 CONFIG_DM_USB=y
+CONFIG_USB_STORAGE=y