goldfish-opengl: one virtgpu instance per HostConnection

When in virtio mode -- even with ASG -- gfxstream opens an ancillary
rendernode fd to perform the process pipe logic.  Reuse the already
existing one from the stream.

BUG=202552093
TEST=compile

Change-Id: I32d2f42afa744ca681aff815d00b3e85158c347b
diff --git a/system/OpenglSystemCommon/HostConnection.h b/system/OpenglSystemCommon/HostConnection.h
index 9d31610..d954c02 100644
--- a/system/OpenglSystemCommon/HostConnection.h
+++ b/system/OpenglSystemCommon/HostConnection.h
@@ -149,7 +149,7 @@
 // Abstraction for process pipe helper
 class ProcessPipe {
 public:
-    virtual bool processPipeInit(HostConnectionType connType, renderControl_encoder_context_t *rcEnc) = 0;
+    virtual bool processPipeInit(int stream_handle, HostConnectionType connType, renderControl_encoder_context_t *rcEnc) = 0;
     virtual ~ProcessPipe() {}
 };