ioat: ring size variables need to be 32bit to avoid overflow

The alloc order can be up to 16 and 1 << 16 will over flow the 16bit
integer. Change the appropriate variables to 16bit to avoid overflow.

Reported-by: Jim Harris <james.r.harris@intel.com>
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
diff --git a/drivers/dma/ioat/dma_v2.c b/drivers/dma/ioat/dma_v2.c
index cb8864d..143cb1b 100644
--- a/drivers/dma/ioat/dma_v2.c
+++ b/drivers/dma/ioat/dma_v2.c
@@ -575,9 +575,9 @@
 	 */
 	struct ioat_chan_common *chan = &ioat->base;
 	struct dma_chan *c = &chan->common;
-	const u16 curr_size = ioat2_ring_size(ioat);
+	const u32 curr_size = ioat2_ring_size(ioat);
 	const u16 active = ioat2_ring_active(ioat);
-	const u16 new_size = 1 << order;
+	const u32 new_size = 1 << order;
 	struct ioat_ring_ent **ring;
 	u16 i;