uas: Allow uas_use_uas_driver to return usb-storage flags

uas: Allow uas_use_uas_driver to return usb-storage flags

[ Upstream commit a5011d44f0e1117a6db14b19b57c51f8be5673a0 ]

uas_use_uas_driver may set some US_FL_foo flags during detection, currently
these are stored in a local variable and then throw away, but these may be
of interest to the caller, so add an extra parameter to (optionally) return
the detected flags, and use this in the uas driver.

Cc: stable@vger.kernel.org # 3.16
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>