mm: collapse security_vm_enough_memory() variants into a single function

Collapse security_vm_enough_memory() variants into a single function.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: James Morris <jmorris@namei.org>
diff --git a/kernel/fork.c b/kernel/fork.c
index f0e7781..d5ebddf 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -355,7 +355,7 @@
 		charge = 0;
 		if (mpnt->vm_flags & VM_ACCOUNT) {
 			unsigned int len = (mpnt->vm_end - mpnt->vm_start) >> PAGE_SHIFT;
-			if (security_vm_enough_memory(len))
+			if (security_vm_enough_memory_mm(oldmm, len)) /* sic */
 				goto fail_nomem;
 			charge = len;
 		}