Merge remote-tracking branch 'remotes/kraxel/tags/usb-20201019-pull-request' into...

usb: fixes for dwc2 + ehci.

# gpg: Signature made Mon 19 Oct 2020 13:33:16 BST
# gpg:                using RSA key 4CB6D8EED3E87138
# gpg: Good signature from "Gerd Hoffmann (work) <kraxel@redhat.com>" [full]
# gpg:                 aka "Gerd Hoffmann <gerd@kraxel.org>" [full]
# gpg:                 aka "Gerd Hoffmann (private) <kraxel@gmail.com>" [full]
# Primary key fingerprint: A032 8CFF B93A 17A7 9901  FE7D 4CB6 D8EE D3E8 7138

* remotes/kraxel/tags/usb-20201019-pull-request:
  hw/usb/hcd-dwc2: fix divide-by-zero in dwc2_handle_packet()
  usb/hcd-ehci: Fix error handling on missing device for iTD
  usb: hcd-dwc2: change assert()s to qemu_log_mask(LOG_GUEST_ERROR...)

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>