fs/proc/kcore.c: Pass a pointer to virt_addr_valid()

The virt_addr_valid() should be passed a pointer, the current
code passing a long unsigned int is just exploiting the
unintentional polymorphism of these calls being implemented
as preprocessor macros.
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

fs/proc/kcore.c

@@ -199,7 +199,7 @@ kclist_add_private(unsigned long pfn, unsigned long nr_pages, void *arg)
 	ent->addr = (unsigned long)page_to_virt(p);
 	ent->size = nr_pages << PAGE_SHIFT;
 
-	if (!virt_addr_valid(ent->addr))
+	if (!virt_addr_valid((void *)ent->addr))
 		goto free_out;
 
 	/* cut not-mapped area. ....from ppc-32 code. */