Description of problem:
USB ethernet adapater activation fails.

lsusb:
Bus 002 Device 031: ID 0b95:1780 ASIX Electronics Corp. AX88178

this is a Level One USB gigabit ethernet adapter

It worked well under F19, so this is a regression.



Version-Release number of selected component (if applicable):
NetworkManager-0.9.9.0-22.git20131003.fc20.x86_64

How reproducible:
always

Steps to Reproduce:
1. plugin in specified USB ethernet adapter (connected to a network) into an USB port
2.
3.

Actual results:
Jan  7 09:01:51 stinkpad NetworkManager[995]: <error> [1389081711.51101] [platform/nm-linux-platform.c:1127] add_object(): Netlink error: Unspecific failure
Jan  7 09:01:51 stinkpad NetworkManager[995]: <info> Activation (enp0s20u3u4u1) Stage 5 of 5 (IPv4 Commit) failed
Jan  7 09:01:51 stinkpad NetworkManager[995]: <info> (enp0s20u3u4u1): device state change: ip-config -> failed (reason 'config-failed') [70 120 4]
Jan  7 09:01:51 stinkpad NetworkManager[995]: <warn> Activation (enp0s20u3u4u1) failed for connection 'Wired connection 1'
Jan  7 09:01:51 stinkpad NetworkManager[995]: <info> Activation (enp0s20u3u4u1) Stage 5 of 5 (IPv4 Commit) complete.


Expected results:
Normal activation



lsusb -v
Bus 002 Device 031: ID 0b95:1780 ASIX Electronics Corp. AX88178
Couldn't open device, some information will be missing
Device Descriptor:
  bLength                18
  bDescriptorType         1
  bcdUSB               2.00
  bDeviceClass          255 Vendor Specific Class
  bDeviceSubClass       255 Vendor Specific Subclass
  bDeviceProtocol         0 
  bMaxPacketSize0        64
  idVendor           0x0b95 ASIX Electronics Corp.
  idProduct          0x1780 AX88178
  bcdDevice            0.01
  iManufacturer           1 
  iProduct                2 
  iSerial                 3 
  bNumConfigurations      1
  Configuration Descriptor:
    bLength                 9
    bDescriptorType         2
    wTotalLength           39
    bNumInterfaces          1
    bConfigurationValue     1
    iConfiguration          4 
    bmAttributes         0xa0
      (Bus Powered)
      Remote Wakeup
    MaxPower              450mA
    Interface Descriptor:
      bLength                 9
      bDescriptorType         4
      bInterfaceNumber        0
      bAlternateSetting       0
      bNumEndpoints           3
      bInterfaceClass       255 Vendor Specific Class
      bInterfaceSubClass    255 Vendor Specific Subclass
      bInterfaceProtocol      0 
      iInterface              7 
      Endpoint Descriptor:
        bLength                 7
        bDescriptorType         5
        bEndpointAddress     0x81  EP 1 IN
        bmAttributes            3
          Transfer Type            Interrupt
          Synch Type               None
          Usage Type               Data
        wMaxPacketSize     0x0008  1x 8 bytes
        bInterval              11
      Endpoint Descriptor:
        bLength                 7
        bDescriptorType         5
        bEndpointAddress     0x82  EP 2 IN
        bmAttributes            2
          Transfer Type            Bulk
          Synch Type               None
          Usage Type               Data
        wMaxPacketSize     0x0200  1x 512 bytes
        bInterval               0
      Endpoint Descriptor:
        bLength                 7
        bDescriptorType         5
        bEndpointAddress     0x03  EP 3 OUT
        bmAttributes            2
          Transfer Type            Bulk
          Synch Type               None
          Usage Type               Data
        wMaxPacketSize     0x0200  1x 512 bytes
        bInterval               0