mpc52xx/wdt: merge WDT code into the GPT driver

Merge the WDT code into the GPT interface.
Signed-off-by: Albrecht Dreß <albrecht.dress@arcor.de>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>

arch/powerpc/include/asm/mpc52xx.h

@@ -281,7 +281,8 @@ struct mpc52xx_gpt_priv;
 extern struct mpc52xx_gpt_priv *mpc52xx_gpt_from_irq(int irq);
 extern int mpc52xx_gpt_start_timer(struct mpc52xx_gpt_priv *gpt, u64 period,
                             int continuous);
-extern void mpc52xx_gpt_stop_timer(struct mpc52xx_gpt_priv *gpt);
+extern u64 mpc52xx_gpt_timer_period(struct mpc52xx_gpt_priv *gpt);
+extern int mpc52xx_gpt_stop_timer(struct mpc52xx_gpt_priv *gpt);
 
 /* mpc52xx_lpbfifo.c */
 #define MPC52XX_LPBFIFO_FLAG_READ		(0)