ACPICA: Update for GCC 4

Fixes several issues with GCC 4.6 related to the new checks for
unused variables.

http://www.acpica.org/bugzilla/show_bug.cgi?id=935

Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Lin Ming <ming.m.lin@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>

drivers/acpi/acpica/utmutex.c

@@ -293,14 +293,10 @@ acpi_status acpi_ut_acquire_mutex(acpi_mutex_handle mutex_id)
 
 acpi_status acpi_ut_release_mutex(acpi_mutex_handle mutex_id)
 {
-	acpi_thread_id this_thread_id;
-
 	ACPI_FUNCTION_NAME(ut_release_mutex);
 
-	this_thread_id = acpi_os_get_thread_id();
-
 	ACPI_DEBUG_PRINT((ACPI_DB_MUTEX, "Thread %u releasing Mutex [%s]\n",
-			  (u32)this_thread_id,
+			  (u32)acpi_os_get_thread_id(),
 			  acpi_ut_get_mutex_name(mutex_id)));
 
 	if (mutex_id > ACPI_MAX_MUTEX) {
@@ -329,7 +325,8 @@ acpi_status acpi_ut_release_mutex(acpi_mutex_handle mutex_id)
 		 * the ACPI subsystem code.
 		 */
 		for (i = mutex_id; i < ACPI_NUM_MUTEX; i++) {
-			if (acpi_gbl_mutex_info[i].thread_id == this_thread_id) {
+			if (acpi_gbl_mutex_info[i].thread_id ==
+			    acpi_os_get_thread_id()) {
 				if (i == mutex_id) {
 					continue;
 				}