gfxstream: Fix compiler warnings

.. for some unused function arguments.

Reviewed-by: Marcin Radomski <dextero@google.com>
Reviewed-by: Aaron Ruby <aruby@qnx.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/35323>

src/gfxstream/guest/android/include/gfxstream/guest/GfxStreamGralloc.h

@@ -177,7 +177,7 @@ class Gralloc {
 
     virtual bool treatBlobAsImage() { return false; }
 
-    virtual int32_t getDataspace(const AHardwareBuffer* ahb) {
+    virtual int32_t getDataspace(const AHardwareBuffer* /*ahb*/) {
         return GFXSTREAM_AHB_DATASPACE_UNKNOWN;
     }
 };

src/gfxstream/guest/iostream/include/gfxstream/guest/IOStream.h

@@ -39,7 +39,7 @@ public:
         return m_bufsize < len ? len : m_bufsize;
     }
 
-    virtual int connect(const char* serviceName = nullptr) { return 0; }
+    virtual int connect(const char* /*serviceName*/ = nullptr) { return 0; }
     virtual uint64_t processPipeInit() { return 0; }
 
     virtual void *allocBuffer(size_t minSize) = 0;