usb: storage: Show number of storage devices detected for DM_USB

By enabling DM_USB information about number of storage devices
was lost.
Get this information back simply by printing number of devices detected
via BLK uclass.

For example:
scanning bus 0 for devices... 7 USB Device(s) found
       scanning usb for storage devices... 3 Storage Device(s) found
       scanning usb for ethernet devices... 0 Ethernet Device(s) found

Signed-off-by: Michal Simek <michal.simek@xilinx.com>
diff --git a/cmd/usb.c b/cmd/usb.c
index 455127c..4fa456e 100644
--- a/cmd/usb.c
+++ b/cmd/usb.c
@@ -571,11 +571,11 @@
 		return;
 
 	/* Driver model will probe the devices as they are found */
-#ifndef CONFIG_DM_USB
 # ifdef CONFIG_USB_STORAGE
 	/* try to recognize storage devices immediately */
 	usb_stor_curr_dev = usb_stor_scan(1);
 # endif
+#ifndef CONFIG_DM_USB
 # ifdef CONFIG_USB_KEYBOARD
 	drv_usb_kbd_init();
 # endif