ACPI / porocessor: Beautify code, pr->id is u32 which is never < 0

pr->id is u32 which never < 0, so remove the redundant pr->id < 0
check from acpi_processor_add().

[rjw: Changelog]
Signed-off-by: NChen Gang <gang.chen@asianux.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

drivers/acpi/processor_driver.c

@@ -559,7 +559,7 @@ static int __cpuinit acpi_processor_add(struct acpi_device *device)
 		return 0;
 #endif
 
-	BUG_ON((pr->id >= nr_cpu_ids) || (pr->id < 0));
+	BUG_ON(pr->id >= nr_cpu_ids);
 
 	/*
 	 * Buggy BIOS check