mesa: Silence GCC warning in count_tex_size

main/texobj.c: In function 'count_tex_size':
main/texobj.c:886:23: warning: unused parameter 'key' [-Wunused-parameter]

Signed-off-by: Ian Romanick <ian.d.romanick@intel.com>
Reviewed-by: Jordan Justen <jordan.l.justen@intel.com>
Reviewed-by: Brian Paul <brianp@vmware.com>

src/mesa/main/texobj.c

@@ -889,6 +889,8 @@ count_tex_size(GLuint key, void *data, void *userData)
       (const struct gl_texture_object *) data;
    GLuint *total = (GLuint *) userData;
 
+   (void) key;
+
    *total = *total + texture_size(texObj);
 }