dmaengine: qcom: bam_dma: use sg_nents_for_dma() helper

Instead of open coded variant let's use recently introduced helper.

Reviewed-by: Bjorn Andersson <andersson@kernel.org>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://patch.msgid.link/20260108105619.3513561-11-andriy.shevchenko@linux.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>

Author: andy-shev

drivers/dma/qcom/bam_dma.c

@@ -653,22 +653,17 @@ static struct dma_async_tx_descriptor *bam_prep_slave_sg(struct dma_chan *chan,
 	struct scatterlist *sg;
 	u32 i;
 	struct bam_desc_hw *desc;
-	unsigned int num_alloc = 0;
-
+	unsigned int num_alloc;
 
 	if (!is_slave_direction(direction)) {
 		dev_err(bdev->dev, "invalid dma direction\n");
 		return NULL;
 	}
 
-	/* calculate number of required entries */
-	for_each_sg(sgl, sg, sg_len, i)
-		num_alloc += DIV_ROUND_UP(sg_dma_len(sg), BAM_FIFO_SIZE);
-
 	/* allocate enough room to accommodate the number of entries */
+	num_alloc = sg_nents_for_dma(sgl, sg_len, BAM_FIFO_SIZE);
 	async_desc = kzalloc(struct_size(async_desc, desc, num_alloc),
 			     GFP_NOWAIT);
-
 	if (!async_desc)
 		return NULL;