gcc-4.6: ACPI: fix unused but set variables in ACPI

Some minor improvements in error handling, but overall it was mostly dead
code.

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Len Brown <len.brown@intel.com>
diff --git a/drivers/acpi/processor_idle.c b/drivers/acpi/processor_idle.c
index 5cbc0cb..07bc74d 100644
--- a/drivers/acpi/processor_idle.c
+++ b/drivers/acpi/processor_idle.c
@@ -722,13 +722,12 @@
 	} else if (cx->entry_method == ACPI_CSTATE_HALT) {
 		acpi_safe_halt();
 	} else {
-		int unused;
 		/* IO port based C-state */
 		inb(cx->address);
 		/* Dummy wait op - must do something useless after P_LVL2 read
 		   because chipsets cannot guarantee that STPCLK# signal
 		   gets asserted in time to freeze execution properly. */
-		unused = inl(acpi_gbl_FADT.xpm_timer_block.address);
+		inl(acpi_gbl_FADT.xpm_timer_block.address);
 	}
 	start_critical_timings();
 }