sw: getting dfu working about to add debug bridge

We're having issues getteing DFU working.  It almost works, but has some
issues.  Unfortunately, we're out of space for printf.

Now we will work to get the UART Wishbone bridge working, to move
forward on debugging support.

Signed-off-by: Sean Cross <sean@xobs.io>

sw/include/dfu.h

@@ -63,7 +63,7 @@ typedef enum {
 
 #define DFU_INTERFACE             0
 #define DFU_DETACH_TIMEOUT        10000     // 10 second timer
-#define DFU_TRANSFER_SIZE         32768     // Flash sector size
+#define DFU_TRANSFER_SIZE         256       // Flash sector size
 
 // Main thread
 void dfu_init();