ARM: lpc3250: config: add generic board support

The only LPC3250 board works fine with enabled generic board support,
add CONFIG_SYS_GENERIC_BOARD right into the arch config header.

Signed-off-by: Vladimir Zapolskiy <vz@mleia.com>

arch/arm/include/asm/arch-lpc32xx/config.h

 /*
  * Common definitions for LPC32XX board configurations
  *
- * Copyright (C) 2011 Vladimir Zapolskiy <vz@mleia.com>
+ * Copyright (C) 2011-2015 Vladimir Zapolskiy <vz@mleia.com>
  *
  * SPDX-License-Identifier:	GPL-2.0+
  */
@@ -9,6 +9,8 @@
 #ifndef _LPC32XX_CONFIG_H
 #define _LPC32XX_CONFIG_H
 
+#define CONFIG_SYS_GENERIC_BOARD
+
 /* Basic CPU architecture */
 #define CONFIG_ARCH_CPU_INIT