[ARM] Fix ioremap.c vfree type warning

arch/arm/mm/ioremap.c:145: warning: passing argument 1 of 'vfree' makes pointer from integer without a cast

resulted from commit id 9d4ae7276a

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

arch/arm/mm/ioremap.c

@@ -142,7 +142,7 @@ __ioremap_pfn(unsigned long pfn, unsigned long offset, size_t size,
  		return NULL;
  	addr = (unsigned long)area->addr;
  	if (remap_area_pages(addr, pfn, size, flags)) {
- 		vfree(addr);
+ 		vfree((void *)addr);
  		return NULL;
  	}
  	return (void __iomem *) (offset + (char *)addr);