platform: x86: Deletion of checks before backlight_device_unregister()

The backlight_device_unregister() function tests whether its argument is NULL
and then returns immediately. Thus the test around the call is not needed.

This issue was detected by using the Coccinelle software.
Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
For msi-wmi.c:
Acked-by: Anisse Astier <anisse@astier.eu>
Signed-off-by: Darren Hart <dvhart@linux.intel.com>

drivers/platform/x86/asus-laptop.c

@@ -843,7 +843,6 @@ static int asus_backlight_init(struct asus_laptop *asus)
 
 static void asus_backlight_exit(struct asus_laptop *asus)
 {
-	if (asus->backlight_device)
 	backlight_device_unregister(asus->backlight_device);
 	asus->backlight_device = NULL;
 }

drivers/platform/x86/asus-wmi.c

@@ -1308,7 +1308,6 @@ static int asus_wmi_backlight_init(struct asus_wmi *asus)
 
 static void asus_wmi_backlight_exit(struct asus_wmi *asus)
 {
-	if (asus->backlight_device)
 	backlight_device_unregister(asus->backlight_device);
 
 	asus->backlight_device = NULL;

drivers/platform/x86/eeepc-laptop.c

@@ -1174,7 +1174,6 @@ static int eeepc_backlight_init(struct eeepc_laptop *eeepc)
 
 static void eeepc_backlight_exit(struct eeepc_laptop *eeepc)
 {
-	if (eeepc->backlight_device)
 	backlight_device_unregister(eeepc->backlight_device);
 	eeepc->backlight_device = NULL;
 }

drivers/platform/x86/fujitsu-laptop.c

@@ -1154,7 +1154,6 @@ static int __init fujitsu_init(void)
 fail_hotkey:
 	platform_driver_unregister(&fujitsupf_driver);
 fail_backlight:
-	if (fujitsu->bl_device)
 	backlight_device_unregister(fujitsu->bl_device);
 fail_sysfs_group:
 	sysfs_remove_group(&fujitsu->pf_device->dev.kobj,
@@ -1179,7 +1178,6 @@ static void __exit fujitsu_cleanup(void)
 
 	platform_driver_unregister(&fujitsupf_driver);
 
-	if (fujitsu->bl_device)
 	backlight_device_unregister(fujitsu->bl_device);
 
 	sysfs_remove_group(&fujitsu->pf_device->dev.kobj,

drivers/platform/x86/ideapad-laptop.c

@@ -729,7 +729,6 @@ static int ideapad_backlight_init(struct ideapad_private *priv)
 
 static void ideapad_backlight_exit(struct ideapad_private *priv)
 {
-	if (priv->blightdev)
 	backlight_device_unregister(priv->blightdev);
 	priv->blightdev = NULL;
 }

drivers/platform/x86/intel_oaktrail.c

@@ -271,7 +271,6 @@ static int oaktrail_backlight_init(void)
 
 static void oaktrail_backlight_exit(void)
 {
-	if (oaktrail_bl_device)
 	backlight_device_unregister(oaktrail_bl_device);
 }
 

drivers/platform/x86/msi-wmi.c

@@ -354,7 +354,6 @@ static void __exit msi_wmi_exit(void)
 		sparse_keymap_free(msi_wmi_input_dev);
 		input_unregister_device(msi_wmi_input_dev);
 	}
-	if (backlight)
 	backlight_device_unregister(backlight);
 }
 

drivers/platform/x86/sony-laptop.c

@@ -3141,7 +3141,6 @@ static void sony_nc_backlight_setup(void)
 
 static void sony_nc_backlight_cleanup(void)
 {
-	if (sony_bl_props.dev)
 	backlight_device_unregister(sony_bl_props.dev);
 }
 

drivers/platform/x86/toshiba_acpi.c

@@ -1797,7 +1797,6 @@ static int toshiba_acpi_remove(struct acpi_device *acpi_dev)
 		rfkill_destroy(dev->bt_rfk);
 	}
 
-	if (dev->backlight_dev)
 	backlight_device_unregister(dev->backlight_dev);
 
 	if (dev->illumination_supported)