USB gadget / dfu fixes

[Sascha Hauer]

This cleans up the error pathes in the USB gadget and dfu layer.

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Sascha Hauer (4):
      USB gadget: at91: return error when no udc is registered
      dfu command: check return values
      USB gadget: fsl: Bail out if no udc exists
      USB gadget: dfu: propagate error from usb_gadget_poll

 commands/dfu.c                | 9 ++++++---
 drivers/usb/gadget/at91_udc.c | 2 +-
 drivers/usb/gadget/dfu.c      | 7 ++++++-
 drivers/usb/gadget/fsl_udc.c  | 3 +++
 4 files changed, 16 insertions(+), 5 deletions(-)