m68k: put definition guards around virt_to_phys and phys_to_virt

The non-MMU and ColdFire IO access functions will be moving to using the
asm-generic/io.h in the near future. To make that possible we need define
guards around the m68k specific virt_to_phys() and phys_to_virt()
functions.
Signed-off-by: Greg Ungerer <gerg@linux-m68k.org>
Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
Reviewed-by: Angelo Dureghello <angelo@sysam.it>
Tested-by: Angelo Dureghello <angelo@sysam.it>

arch/m68k/include/asm/virtconvert.h

@@ -16,11 +16,13 @@
 /*
  * Change virtual addresses to physical addresses and vv.
  */
+#define virt_to_phys virt_to_phys
 static inline unsigned long virt_to_phys(void *address)
 {
 	return __pa(address);
 }
 
+#define phys_to_virt phys_to_virt
 static inline void *phys_to_virt(unsigned long address)
 {
 	return __va(address);