ARM64: zynqmp: Define config USB_STORAGE through defconfig

Define config USB_STORAGE through defconfig for all
Xilinx ZynqMP boards.

Signed-off-by: Michal Simek <michal.simek@xilinx.com>
diff --git a/configs/xilinx_zynqmp_zc1751_xm015_dc1_defconfig b/configs/xilinx_zynqmp_zc1751_xm015_dc1_defconfig
index 27b6b8d..0700ec2 100644
--- a/configs/xilinx_zynqmp_zc1751_xm015_dc1_defconfig
+++ b/configs/xilinx_zynqmp_zc1751_xm015_dc1_defconfig
@@ -60,6 +60,7 @@
 CONFIG_USB_DWC3_GADGET=y
 CONFIG_USB_ULPI_VIEWPORT=y
 CONFIG_USB_ULPI=y
+CONFIG_USB_STORAGE=y
 CONFIG_USB_GADGET=y
 CONFIG_USB_GADGET_DOWNLOAD=y
 CONFIG_G_DNL_MANUFACTURER="Xilinx"