Instead of sending both IRP_MN_SURPRISE_REMOVAL and IRP_MN_REMOVE_DEVICE
to all children first.

They may have pending IRPs sent to their parent PDO driver, which need
to be cancelled before IRP_MN_REMOVE_DEVICE can complete. This is the
case for hidclass.sys and its thread calling the lower driver for
instance.
Signed-off-by: Rémi Bernon <rbernon@codeweavers.com>
Signed-off-by: Zebediah Figura <zfigura@codeweavers.com>
Signed-off-by: Alexandre Julliard <julliard@winehq.org>