mm/memcontrol.c: remove the useless parameter for mc_handle_swap_pte

It seems like this parameter has never been used since being introduced
by 90254a6583 ("memcg: clean up move charge").  Not a big deal because
I assume the function would get inlined into the caller anyway but why
not get rid of it.

[mhocko@suse.com: wrote changelog]
  Link: http://lkml.kernel.org/r/20160525151831.GJ20132@dhcp22.suse.cz
Link: http://lkml.kernel.org/r/1464145026-26693-1-git-send-email-roy.qing.li@gmail.com
Signed-off-by: Li RongQing <roy.qing.li@gmail.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

mm/memcontrol.c

@@ -4409,7 +4409,7 @@ static struct page *mc_handle_present_pte(struct vm_area_struct *vma,
 
 #ifdef CONFIG_SWAP
 static struct page *mc_handle_swap_pte(struct vm_area_struct *vma,
-			unsigned long addr, pte_t ptent, swp_entry_t *entry)
+			pte_t ptent, swp_entry_t *entry)
 {
 	struct page *page = NULL;
 	swp_entry_t ent = pte_to_swp_entry(ptent);
@@ -4428,7 +4428,7 @@ static struct page *mc_handle_swap_pte(struct vm_area_struct *vma,
 }
 #else
 static struct page *mc_handle_swap_pte(struct vm_area_struct *vma,
-			unsigned long addr, pte_t ptent, swp_entry_t *entry)
+			pte_t ptent, swp_entry_t *entry)
 {
 	return NULL;
 }
@@ -4593,7 +4593,7 @@ static enum mc_target_type get_mctgt_type(struct vm_area_struct *vma,
 	if (pte_present(ptent))
 		page = mc_handle_present_pte(vma, addr, ptent);
 	else if (is_swap_pte(ptent))
-		page = mc_handle_swap_pte(vma, addr, ptent, &ent);
+		page = mc_handle_swap_pte(vma, ptent, &ent);
 	else if (pte_none(ptent))
 		page = mc_handle_file_pte(vma, addr, ptent, &ent);