GraphicBufferAlloc class was declared twice

this was confusing because the one in FramebufferSurface
wasn't in fact being used

Change-Id: Ied45aec20d804cfbe52440f9b2f2852a85c757cf
diff --git a/services/surfaceflinger/Android.mk b/services/surfaceflinger/Android.mk
index 07002cc..6db89f0 100644
--- a/services/surfaceflinger/Android.mk
+++ b/services/surfaceflinger/Android.mk
@@ -11,6 +11,7 @@
     LayerDim.cpp                            \
     LayerScreenshot.cpp                     \
     DisplayHardware/FramebufferSurface.cpp  \
+    DisplayHardware/GraphicBufferAlloc.cpp  \
     DisplayHardware/HWComposer.cpp          \
     DisplayHardware/PowerHAL.cpp            \
     GLExtensions.cpp                        \