um: Fix kmalloc argument order in um/vdso/vma.c

kmalloc size is 1st arg, not second.
Signed-off-by: Dave Jones <davej@redhat.com>
Signed-off-by: Richard Weinberger <richard@nod.at>

Cc: <stable@kernel.org> # 3.0.x
[richard@nod.at: on 3.0 the to be patched file is
arch/um/sys-x86_64/vdso/vma.c]

arch/x86/um/vdso/vma.c

@@ -28,7 +28,7 @@ static int __init init_vdso(void)
 
 	um_vdso_addr = task_size - PAGE_SIZE;
 
-	vdsop = kmalloc(GFP_KERNEL, sizeof(struct page *));
+	vdsop = kmalloc(sizeof(struct page *), GFP_KERNEL);
 	if (!vdsop)
 		goto oom;