pinctrl: mvebu: Use kmalloc_array() in mvebu_pinctrl_dt_node_to_map()

* 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 by using the Coccinelle software.

* Replace the specification of a data structure by a pointer dereference
  to make the corresponding size determination a bit safer according to
  the Linux coding style convention.
Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

drivers/pinctrl/mvebu/pinctrl-mvebu.c

@@ -398,7 +398,7 @@ static int mvebu_pinctrl_dt_node_to_map(struct pinctrl_dev *pctldev,
 		return 0;
 	}
 
-	*map = kmalloc(nmaps * sizeof(struct pinctrl_map), GFP_KERNEL);
+	*map = kmalloc_array(nmaps, sizeof(**map), GFP_KERNEL);
 	if (*map == NULL) {
 		dev_err(pctl->dev,
 			"cannot allocate pinctrl_map memory for %s\n",