USB: visor: increase bulk-out buffer size

Increase the bulk-out buffer size to avoid any regression in throughput
after replacing the old writing scheme which used dynamic buffers (e.g.
up to 2k).

256b has been determined to be a good choice for several drivers
including ftdi_sio which used to have a more or less identical write
implementation.
Signed-off-by: NJohan Hovold <jhovold@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

drivers/usb/serial/visor.c

@@ -186,6 +186,7 @@ static struct usb_serial_driver handspring_device = {
 	.usb_driver =		&visor_driver,
 	.id_table =		id_table,
 	.num_ports =		2,
+	.bulk_out_size =	256,
 	.open =			visor_open,
 	.close =		visor_close,
 	.throttle =		usb_serial_generic_throttle,
@@ -206,6 +207,7 @@ static struct usb_serial_driver clie_5_device = {
 	.usb_driver =		&visor_driver,
 	.id_table =		clie_id_5_table,
 	.num_ports =		2,
+	.bulk_out_size =	256,
 	.open =			visor_open,
 	.close =		visor_close,
 	.throttle =		usb_serial_generic_throttle,
@@ -226,6 +228,7 @@ static struct usb_serial_driver clie_3_5_device = {
 	.usb_driver =		&visor_driver,
 	.id_table =		clie_id_3_5_table,
 	.num_ports =		1,
+	.bulk_out_size =	256,
 	.open =			visor_open,
 	.close =		visor_close,
 	.throttle =		usb_serial_generic_throttle,