Convert CONFIG_USB_KEYBOARD to Kconfig

This converts the following to Kconfig:
   CONFIG_USB_KEYBOARD

Signed-off-by: Simon Glass <sjg@chromium.org>
[trini: Fixup MPC86* configs]
Signed-off-by: Tom Rini <trini@konsulko.com>
diff --git a/configs/novena_defconfig b/configs/novena_defconfig
index 6b469b1..a521542 100644
--- a/configs/novena_defconfig
+++ b/configs/novena_defconfig
@@ -37,6 +37,7 @@
 CONFIG_CMD_FS_GENERIC=y
 CONFIG_USB=y
 CONFIG_USB_STORAGE=y
+CONFIG_USB_KEYBOARD=y
 CONFIG_USB_GADGET=y
 CONFIG_CI_UDC=y
 # CONFIG_VIDEO_SW_CURSOR is not set