common/board_f.c: align m68k arch to use CONFIG_DISPLAY_CPUINFO

Change all coldfire arch files to use CONFIG_DISPLAY_CPUINFO.

Signed-off-by: Angelo Dureghello <angelo@sysam.it>
Reviewed-by: Tom Rini <trini@konsulko.com>
---
Changes for v2:
   - update common/Kconfig to add M68K to the default y list
diff --git a/arch/m68k/cpu/mcf530x/cpu.c b/arch/m68k/cpu/mcf530x/cpu.c
index 78f4385..3552af2 100644
--- a/arch/m68k/cpu/mcf530x/cpu.c
+++ b/arch/m68k/cpu/mcf530x/cpu.c
@@ -25,7 +25,8 @@
 	return 0;
 }
 
-int checkcpu(void)
+#if defined(CONFIG_DISPLAY_CPUINFO)
+int print_cpuinfo(void)
 {
 	char buf[32];
 
@@ -33,4 +34,5 @@
 	       strmhz(buf, CONFIG_SYS_CPU_CLK));
 	return 0;
 }
+#endif /* CONFIG_DISPLAY_CPUINFO */
 #endif