[U-Boot] rockchip: Add USB to the default boot targets

[Eddie Cai]

Now that most rockchip SoC based board have usb host support, enable
USB boot targets by default.

Signed-off-by: Eddie Cai <eddie.cai.linux at gmail.com>
---
 include/configs/rockchip-common.h | 1 +
 1 file changed, 1 insertion(+)

diff --git a/include/configs/rockchip-common.h b/include/configs/rockchip-common.h
index fd930c1..41967dd 100644
--- a/include/configs/rockchip-common.h
+++ b/include/configs/rockchip-common.h
@@ -15,6 +15,7 @@
 #define BOOT_TARGET_DEVICES(func) \
 	func(MMC, mmc, 0) \
 	func(MMC, mmc, 1) \
+	func(USB, usb, 0) \
 	func(PXE, pxe, na) \
 	func(DHCP, dchp, na)
 
-- 
2.10.2