USB: storage: fix wording in error message

Make it obvious that the UAS driver is being ignored for a specific
device by fixing up the wording to be more clear.

Cc: Alan Stern <stern@rowland.harvard.edu>
Link: https://lore.kernel.org/r/20200618094300.1887727-7-gregkh@linuxfoundation.org


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>