regulator: axp20x: add NULL check on devm_kzalloc() return value

Check return value from call to devm_kzalloc()
in order to prevent a NULL pointer dereference.

This issue was detected using Coccinelle and the following semantic patch:

@@
expression x;
identifier fld;
@@

* x = devm_kzalloc(...);
  ... when != x == NULL
  x->fld
Signed-off-by: NGustavo A. R. Silva <garsilva@embeddedor.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

drivers/regulator/axp20x-regulator.c

@@ -691,6 +691,9 @@ static int axp20x_regulator_probe(struct platform_device *pdev)
 		    (regulators == axp809_regulators && i == AXP809_DC1SW)) {
 			new_desc = devm_kzalloc(&pdev->dev, sizeof(*desc),
 						GFP_KERNEL);
+			if (!new_desc)
+				return -ENOMEM;
+
 			*new_desc = regulators[i];
 			new_desc->supply_name = dcdc1_name;
 			desc = new_desc;
@@ -700,6 +703,9 @@ static int axp20x_regulator_probe(struct platform_device *pdev)
 		    (regulators == axp809_regulators && i == AXP809_DC5LDO)) {
 			new_desc = devm_kzalloc(&pdev->dev, sizeof(*desc),
 						GFP_KERNEL);
+			if (!new_desc)
+				return -ENOMEM;
+
 			*new_desc = regulators[i];
 			new_desc->supply_name = dcdc5_name;
 			desc = new_desc;