ideapad_laptop: Introduce the use of the managed version of kzalloc

This patch moves data allocated using kzalloc to managed data allocated
using devm_kzalloc and cleans now unnecessary kfrees in probe and remove
functions. The label sysfs_failed is removed as it is no longer
required.  Also, linux/device.h is added to make sure the devm_*()
routine declarations are unambiguously available.

The following Coccinelle semantic patch was used for making the change:

@platform@
identifier p, probefn, removefn;
@@
struct platform_driver p = {
  .probe = probefn,
  .remove = removefn,
};

@prb@
identifier platform.probefn, pdev;
expression e, e1, e2;
@@
probefn(struct platform_device *pdev, ...) {
  <+...
- e = kzalloc(e1, e2)
+ e = devm_kzalloc(&pdev->dev, e1, e2)
  ...
?-kfree(e);
  ...+>
}

@rem depends on prb@
identifier platform.removefn;
expression e;
@@
removefn(...) {
  <...
- kfree(e);
  ...>
}

Signed-off-by: Himangi Saraogi <himangi774@gmail.com>
Acked-by: Julia Lawall <julia.lawall@lip6.fr>
Signed-off-by: Matthew Garrett <matthew.garrett@nebula.com>

drivers/platform/x86/ideapad-laptop.c

@@ -37,6 +37,7 @@
 #include <linux/seq_file.h>
 #include <linux/i8042.h>
 #include <linux/dmi.h>
+#include <linux/device.h>
 
 #define IDEAPAD_RFKILL_DEV_NUM	(3)
 
@@ -847,7 +848,7 @@ static int ideapad_acpi_add(struct platform_device *pdev)
 	if (read_method_int(adev->handle, "_CFG", &cfg))
 		return -ENODEV;
 
-	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
+	priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
 	if (!priv)
 		return -ENOMEM;
 
@@ -858,7 +859,7 @@ static int ideapad_acpi_add(struct platform_device *pdev)
 
 	ret = ideapad_sysfs_init(priv);
 	if (ret)
-		goto sysfs_failed;
+		return ret;
 
 	ret = ideapad_debugfs_init(priv);
 	if (ret)
@@ -897,8 +898,6 @@ input_failed:
 	ideapad_debugfs_exit(priv);
 debugfs_failed:
 	ideapad_sysfs_exit(priv);
-sysfs_failed:
-	kfree(priv);
 	return ret;
 }
 
@@ -916,7 +915,6 @@ static int ideapad_acpi_remove(struct platform_device *pdev)
 	ideapad_debugfs_exit(priv);
 	ideapad_sysfs_exit(priv);
 	dev_set_drvdata(&pdev->dev, NULL);
-	kfree(priv);
 
 	return 0;
 }