Add board/redbee-usb.cfg

The Redbee USB is a small form-factor usb stick from Redwire, LLC
(www.redwirellc.com/store), built around a Freescale MC13224V
ARM7TDMI + 802.15.4 radio (plus antenna).

It includes an FT2232H for debugging, with Channel B connected to the
mc13224v's JTAG interface (unusual) and Channel A connected to UART1.

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>

src/jtag/drivers/ft2232.c

@@ -269,6 +269,11 @@ static const struct ft2232_layout  ft2232_layouts[] =
 		.init = redbee_init,
 		.reset = redbee_reset,
 	},
+	{ .name = "redbee-usb",
+		.init = redbee_init,
+	        .reset = redbee_reset,
+    	        .channel = INTERFACE_B,
+	},
 	{ .name = NULL, /* END OF TABLE */ },
 };