usb/hcd: Send a uevent signaling that the host controller had died

usb/hcd: Send a uevent signaling that the host controller had died

This change will send an OFFLINE event to udev with the ERROR=DEAD
environment variable set when the HC dies.

By notifying user space the appropriate policies can be applied.
i.e.,
 * Collect error logs.
 * Notify the user that USB is no longer functional.
 * Perform a graceful reboot.

Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Raul E Rangel <rrangel@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>