Only set acquire fences on overlay layers

Change-Id: I08e8173f83580de5a4e43a0ba5ea03e5ec6e8782
diff --git a/services/surfaceflinger/LayerBase.cpp b/services/surfaceflinger/LayerBase.cpp
index fd4c223..8350d27 100644
--- a/services/surfaceflinger/LayerBase.cpp
+++ b/services/surfaceflinger/LayerBase.cpp
@@ -299,6 +299,10 @@
     layer.setBuffer(0);
 }
 
+void LayerBase::setAcquireFence(HWComposer::HWCLayerInterface& layer) {
+    layer.setAcquireFenceFd(-1);
+}
+
 void LayerBase::setFiltering(bool filtering)
 {
     mFiltering = filtering;