usb: r8a66597-hcd: decrease timeout

The timeout for BULK packets was 300ms which is a long time if other
endpoints or devices are waiting for their turn. Changing it to 50ms
greatly increased the overall performance for multi-endpoint devices.

Fixes: 5d304358 ("usb: r8a66597-hcd: host controller driver for R8A6659")
Signed-off-by: Chris Brandt <chris.brandt@renesas.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>