configs: am65x_evm: Enable USB keyboard as second stdin

Enable USB keyboard to be used as input device at U-Boot prompt. Both
serial and USB keyboard will be active inputs simultaneously.

Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com>
Signed-off-by: Lokesh Vutla <lokeshvutla@ti.com>
diff --git a/include/configs/am65x_evm.h b/include/configs/am65x_evm.h
index 9a120ca..7d7f86a 100644
--- a/include/configs/am65x_evm.h
+++ b/include/configs/am65x_evm.h
@@ -72,6 +72,7 @@
 	"overlayaddr=0x83000000\0"					\
 	"name_kern=Image\0"						\
 	"console=ttyS2,115200n8\0"					\
+	"stdin=serial,usbkbd\0"						\
 	"args_all=setenv optargs earlycon=ns16550a,mmio32,0x02800000\0" \
 	"run_kern=booti ${loadaddr} ${rd_spec} ${fdtaddr}\0"		\