resource/PCI: mark struct resource as const

Now that we return the new resource start position, there is no
need to update "struct resource" inside the align function.
Therefore, mark the struct resource as const.

Cc: Bjorn Helgaas <bjorn.helgaas@hp.com>
Cc: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>

arch/arm/kernel/bios32.c

@@ -616,7 +616,7 @@ char * __init pcibios_setup(char *str)
  * but we want to try to avoid allocating at 0x2900-0x2bff
  * which might be mirrored at 0x0100-0x03ff..
  */
-resource_size_t pcibios_align_resource(void *data, struct resource *res,
+resource_size_t pcibios_align_resource(void *data, const struct resource *res,
 				resource_size_t size, resource_size_t align)
 {
 	resource_size_t start = res->start;