emulator opengl: Added glUtilsPixelBitSize function to glUtils.

moved pixel size calculation from GLClientState to glUtils to be used
outside the client state scope. (needed for the renderControl encoder
which will follow in next commit).

Change-Id: I5adbc40b241537054c6743e2afc52ba44454664f

tools/emulator/opengl/shared/OpenglCodecCommon/glUtils.h

@@ -49,6 +49,7 @@ extern "C" {
     void   glUtilsPackPointerData(unsigned char *dst, unsigned char *str,
                            int size, GLenum type, unsigned int stride,
                            unsigned int datalen);
+    int glUtilsPixelBitSize(GLenum format, GLenum type);
 #ifdef __cplusplus
 };
 #endif