ACPIPHP / radeon / nouveau: Remove acpi_bus_no_hotplug()

Revert parts of f244d8b623da ("ACPIPHP / radeon / nouveau: Fix VGA
switcheroo problem related to hotplug").

A previous commit 5493b31f0b55 ("PCI: Add pci_ignore_hotplug() to ignore
hotplug events for a device") added equivalent functionality implemented in
a different way for both acpiphp and pciehp.

Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Alex Deucher <alexander.deucher@amd.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Dave Airlie <airlied@redhat.com>
Acked-by: Rajat Jain <rajatxjain@gmail.com>
diff --git a/drivers/gpu/drm/radeon/radeon_atpx_handler.c b/drivers/gpu/drm/radeon/radeon_atpx_handler.c
index a9fb0d0..8bc7d0b 100644
--- a/drivers/gpu/drm/radeon/radeon_atpx_handler.c
+++ b/drivers/gpu/drm/radeon/radeon_atpx_handler.c
@@ -33,7 +33,6 @@
 	bool atpx_detected;
 	/* handle for device - and atpx */
 	acpi_handle dhandle;
-	acpi_handle other_handle;
 	struct radeon_atpx atpx;
 } radeon_atpx_priv;
 
@@ -453,10 +452,9 @@
 		return false;
 
 	status = acpi_get_handle(dhandle, "ATPX", &atpx_handle);
-	if (ACPI_FAILURE(status)) {
-		radeon_atpx_priv.other_handle = dhandle;
+	if (ACPI_FAILURE(status))
 		return false;
-	}
+
 	radeon_atpx_priv.dhandle = dhandle;
 	radeon_atpx_priv.atpx.handle = atpx_handle;
 	return true;
@@ -540,16 +538,6 @@
 		printk(KERN_INFO "VGA switcheroo: detected switching method %s handle\n",
 		       acpi_method_name);
 		radeon_atpx_priv.atpx_detected = true;
-		/*
-		 * On some systems hotplug events are generated for the device
-		 * being switched off when ATPX is executed.  They cause ACPI
-		 * hotplug to trigger and attempt to remove the device from
-		 * the system, which causes it to break down.  Prevent that from
-		 * happening by setting the no_hotplug flag for the involved
-		 * ACPI device objects.
-		 */
-		acpi_bus_no_hotplug(radeon_atpx_priv.dhandle);
-		acpi_bus_no_hotplug(radeon_atpx_priv.other_handle);
 		return true;
 	}
 	return false;