USB: additional regression fix for device removal

USB: additional regression fix for device removal

commit ca5c485f55d326d9a23e4badd05890148aa53f74 upstream.

Commit e534c5b831c8b8e9f5edee5c8a37753c808b80dc (USB: fix regression
occurring during device removal) didn't go far enough.  It failed to
take into account that when a driver claims multiple interfaces, it may
release them all at the same time.  As a result, some interfaces can
get released before they are unregistered, and we deadlock trying to
acquire the bandwidth_mutex that we already own.

This patch (asl478) handles this case by setting the "unregistering"
flag on all the interfaces before removing any of them.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Tested-by: Éric Piel <eric.piel@tremplin-utc.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>