ste_dma40: Use kmalloc_array() in d40_hw_detect_init()

A multiplication for the size determination of a memory allocation
indicated that an array data structure should be processed.
Thus use the corresponding function "kmalloc_array".

This issue was detected also by using the Coccinelle software.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

drivers/dma/ste_dma40.c

@@ -3301,9 +3301,9 @@ static struct d40_base * __init d40_hw_detect_init(struct platform_device *pdev)
 	if (!base->lookup_log_chans)
 		goto failure;
 
-	base->reg_val_backup_chan = kmalloc(base->num_phy_chans *
-					    sizeof(d40_backup_regs_chan),
-					    GFP_KERNEL);
+	base->reg_val_backup_chan = kmalloc_array(base->num_phy_chans,
+						  sizeof(d40_backup_regs_chan),
+						  GFP_KERNEL);
 	if (!base->reg_val_backup_chan)
 		goto failure;