usbtty: adapt buffers for large packet support

Increase buffer sizes at driver and tty level to accommodate kermit
large packet support.

Signed-off-by: Shiraz Hashim <shiraz.hashim@st.com>

drivers/serial/usbtty.c

@@ -63,7 +63,7 @@
 /*
  * Buffers to hold input and output data
  */
-#define USBTTY_BUFFER_SIZE 256
+#define USBTTY_BUFFER_SIZE 2048
 static circbuf_t usbtty_input;
 static circbuf_t usbtty_output;
 

include/usbdevice.h

@@ -475,7 +475,9 @@ typedef struct urb_link {
  * function driver to inform it that data has arrived.
  */
 
-#define URB_BUF_SIZE 128 /* in linux we'd malloc this, but in u-boot we prefer static data */
+/* in linux we'd malloc this, but in u-boot we prefer static data */
+#define URB_BUF_SIZE 512
+
 struct urb {
 
 	struct usb_endpoint_instance *endpoint;