[ACPI] fix HP nx8220 boot hang regression

This patch reverts the acpi_bus_find_driver() return value check
that came in via the PCI tree via 3fb0273

        [PATCH] acpi bridge hotadd: Allow ACPI .add and .start
	operations to be done independently

This particular change broke booting of some HP/Compaq laptops unless
acpi=noirq is used.

http://bugzilla.kernel.org/show_bug.cgi?id=5221
https://bugzilla.novell.com/show_bug.cgi?id=116763

Signed-off-by: Thomas Renninger <trenn@suse.de>
Cc: Rajesh Shah <rajesh.shah@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>

drivers/acpi/scan.c

@@ -1110,7 +1110,7 @@ acpi_add_single_object(struct acpi_device **child,
 	 *
 	 * TBD: Assumes LDM provides driver hot-plug capability.
 	 */
-	result = acpi_bus_find_driver(device);
+	acpi_bus_find_driver(device);
 
       end:
 	if (!result)