UsbForward: re-init libusb until device is correctly detected.

This change makes libusb to re-enumerate USB devices whenever gadget is
unavailable. libusb is unable to report a device presence, if device
modifies its vendor and product ID on the fly.

Test:
  cd /config/usb_gadget/g1
  while (( 1 )); do
    echo > UDC
    sleep 5
    echo dummy_udc.0 > UDC
    sleep 5
  done

Change-Id: I9bd184d3949cabdf2b92e7d28def63d6311be246
3 files changed
tree: 21f77ed3c692acc5d3ed630530747d3579aad6fc
  1. common/
  2. external/
  3. guest/
  4. host/
  5. tools/
  6. BUILD
  7. WORKSPACE