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/dms-ba16_defconfig b/configs/dms-ba16_defconfig
index e9b0fab..c460f60 100644
--- a/configs/dms-ba16_defconfig
+++ b/configs/dms-ba16_defconfig
@@ -28,6 +28,7 @@
 CONFIG_SPI_FLASH=y
 CONFIG_SPI_FLASH_STMICRO=y
 CONFIG_USB=y
+CONFIG_USB_KEYBOARD=y
 CONFIG_USB_GADGET=y
 CONFIG_CI_UDC=y
 CONFIG_USB_GADGET_DOWNLOAD=y