board_f: prevent misleading "Watchdog enabled" output

Output the "Watchdog enabled" message only if hw_watchdog_init()
call really happened.

Signed-off-by: Anatolij Gustschin <agust@denx.de>

common/board_f.c

@@ -120,8 +120,8 @@ static int init_func_watchdog_init(void)
 	defined(CONFIG_DESIGNWARE_WATCHDOG) || \
 	defined(CONFIG_IMX_WATCHDOG))
 	hw_watchdog_init();
-# endif
 	puts("       Watchdog enabled\n");
+# endif
 	WATCHDOG_RESET();
 
 	return 0;