verstage: provide support for serial console

verstage previously lacked serial console support.
Add the necessary objects and macro checks to allow
verstage to include the serial console.

Change-Id: Ibe911ad347cac0b089f5bc0d4263956f44f3d116
Signed-off-by: Aaron Durbin <adurbin@chromium.org>
Reviewed-on: http://review.coreboot.org/10196
Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>
Tested-by: build bot (Jenkins)

src/include/console/uart.h

@@ -56,7 +56,7 @@ static inline void *uart_platform_baseptr(int idx)
 void oxford_remap(unsigned int new_base);
 
 #define __CONSOLE_SERIAL_ENABLE__	CONFIG_CONSOLE_SERIAL && \
-	(ENV_BOOTBLOCK || ENV_ROMSTAGE || ENV_RAMSTAGE || \
+	(ENV_BOOTBLOCK || ENV_ROMSTAGE || ENV_RAMSTAGE || ENV_VERSTAGE || \
 	(ENV_SMM && CONFIG_DEBUG_SMI))
 
 #if __CONSOLE_SERIAL_ENABLE__