octeon_ep: use vmalloc_array and vcalloc

Use vmalloc_array and vcalloc to protect against
multiplication overflows.

The changes were done using the following Coccinelle
semantic patch:

// <smpl>
@initialize:ocaml@
@@

let rename alloc =
  match alloc with
    "vmalloc" -> "vmalloc_array"
  | "vzalloc" -> "vcalloc"
  | _ -> failwith "unknown"

@@
    size_t e1,e2;
    constant C1, C2;
    expression E1, E2, COUNT, x1, x2, x3;
    typedef u8;
    typedef __u8;
    type t = {u8,__u8,char,unsigned char};
    identifier alloc = {vmalloc,vzalloc};
    fresh identifier realloc = script:ocaml(alloc) { rename alloc };
@@

(
      alloc(x1*x2*x3)
|
      alloc(C1 * C2)
|
      alloc((sizeof(t)) * (COUNT), ...)
|
-     alloc((e1) * (e2))
+     realloc(e1, e2)
|
-     alloc((e1) * (COUNT))
+     realloc(COUNT, e1)
|
-     alloc((E1) * (E2))
+     realloc(E1, E2)
)
// </smpl>

Signed-off-by: Julia Lawall <Julia.Lawall@inria.fr>
Link: https://lore.kernel.org/r/20230627144339.144478-3-Julia.Lawall@inria.fr
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

drivers/net/ethernet/marvell/octeon_ep/octep_rx.c

@@ -158,7 +158,7 @@ static int octep_setup_oq(struct octep_device *oct, int q_no)
 		goto desc_dma_alloc_err;
 	}
 
-	oq->buff_info = vzalloc(oq->max_count * OCTEP_OQ_RECVBUF_SIZE);
+	oq->buff_info = vcalloc(oq->max_count, OCTEP_OQ_RECVBUF_SIZE);
 	if (unlikely(!oq->buff_info)) {
 		dev_err(&oct->pdev->dev,
 			"Failed to allocate buffer info for OQ-%d\n", q_no);