USB: usbtest: use URB_ZERO_PACKET for BULK-OUT transfers
USB: usbtest: use URB_ZERO_PACKET for BULK-OUT transfers

Executing
| testusb -a -c 1 -t 3 -v 421 -s 2048

does not complete on the gadget side.
g_zero enqueues a 4096 bytes long buffer. The host sends 2048bytes which
is a multiple of wMaxPacketSize (either 64 or 512 bytes). The host is
done with sending data but the gadget waits for more.
Since the protocol does not include transfer-length-field sending a
terminating zero packet seems the only way out.

Reviewed-by: Felipe Balbi <94dddeeef08b001e003cce128ddc162a4e2c6cd2@ti.com>
Signed-off-by: Sebastian Andrzej Siewior <265264fed90bdf8e813a354375ec16f47ebdb1c5@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <4645f7897fd33786a2ee1264d590b3c400559d85@suse.de>

KristFoundation/Programs,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas