[PATCH] usb_storage: make usb-stor-scan task non-freezable

From: Seth Forshee
Date: Mon Jul 18 2011 - 12:28:30 EST

The following patch is in response to a consistently reproducible
failure to freeze tasks prior to restoring a hibernation image on a
Toshiba NB505 netbook. This machine has a built-in USB card reader.
Since the usb-stor-scan task is freezable but the code in
quiesce_and_remove_host() that waits for scanning to complete is not,
khubd can fail to freeze when processing the disconnect for the card

It seems that both should either be freezable or not freezable. Since
there doesn't currently seem to be any freezable way to wait on a
completion, I started with the simpler approach of making usb-stor-scan
non-freezable. If it would be preferable to make both freezable I can
take that approach instead.