If suspend callback fails in system sleep context, usb core will
ignore the failure and let the system sleep go ahead further, so this
patch doesn't recover device under this situation, otherwise
may cause resume() confused.
Acked-by: NJiri Kosina <jkosina@suse.cz>
Signed-off-by: NMing Lei <ming.lei@canonical.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>