sandbox: Enable USB keyboard

Enable the USB keyboard on sandbox, now that we have a suitable emulation
driver.
Signed-off-by: Simon Glass <sjg@chromium.org>

configs/sandbox_defconfig

@@ -63,6 +63,8 @@ CONFIG_USB=y
 CONFIG_DM_USB=y
 CONFIG_USB_EMUL=y
 CONFIG_USB_STORAGE=y
+CONFIG_USB_KEYBOARD=y
+CONFIG_SYS_USB_EVENT_POLL=y
 CONFIG_SYS_VSNPRINTF=y
 CONFIG_CMD_DHRYSTONE=y
 CONFIG_TPM=y

include/configs/sandbox.h

@@ -177,7 +177,7 @@
 
 #define CONFIG_KEYBOARD
 
-#define SANDBOX_SERIAL_SETTINGS		"stdin=serial,cros-ec-keyb\0" \
+#define SANDBOX_SERIAL_SETTINGS		"stdin=serial,cros-ec-keyb,usbkbd\0" \
 					"stdout=serial,lcd\0" \
 					"stderr=serial,lcd\0"
 #else