kc1: MUSB USB controller and fastboot USB gadget support

This adds support for the MUSB USB dual-role controller in peripheral mode,
with configuration options for the fastboot USB gadget.

At this point, flashing the internal eMMC is support.

Signed-off-by: Paul Kocialkowski <contact@paulk.fr>
diff --git a/board/amazon/kc1/kc1.h b/board/amazon/kc1/kc1.h
index 886bd38..67d008f 100644
--- a/board/amazon/kc1/kc1.h
+++ b/board/amazon/kc1/kc1.h
@@ -87,6 +87,10 @@
 	{ UNIPRO_RY1,		(IEN  | DIS | M3) }, /* gpio_178 */
 	{ UNIPRO_RX2,		(IDIS | DIS | M7) }, /* safe_mode */
 	{ UNIPRO_RY2,		(IDIS | DIS | M7) }, /* safe_mode */
+	/* USBA0_OTG */
+	{ USBA0_OTG_CE,		(IDIS | PTD | M0) }, /* usba0_otg_ce */
+	{ USBA0_OTG_DP,		(IEN  | DIS | M0) }, /* usba0_otg_dp */
+	{ USBA0_OTG_DM,		(IEN  | DIS | M0) }, /* usba0_otg_dm */
 };
 
 #endif