Revert "ACPICA: revert "acpi_serialize" changes"

This reverts commit a8f4af6dc6600980885c594f52eecd60edd62013.
Thus restoring ACPICA's new acpi_serialize code.

This commit by itself may cause a regression, but
it is reverted in this order so that subsequent
reverts reverts under this one can be made
without conflict.

Signed-off-by: Len Brown <len.brown@intel.com>
diff --git a/drivers/acpi/events/evxface.c b/drivers/acpi/events/evxface.c
index a3379ba..685a103 100644
--- a/drivers/acpi/events/evxface.c
+++ b/drivers/acpi/events/evxface.c
@@ -768,11 +768,9 @@
 		return (AE_BAD_PARAMETER);
 	}
 
-	status = acpi_ex_enter_interpreter();
-	if (ACPI_FAILURE(status)) {
-		return (status);
-	}
+	/* Must lock interpreter to prevent race conditions */
 
+	acpi_ex_enter_interpreter();
 	status = acpi_ev_acquire_global_lock(timeout);
 	acpi_ex_exit_interpreter();