../lib/igt_fb.c: In function ‘convert_rgb24_to_yuv444’:
../lib/igt_fb.c:1720:16: warning: unused variable ‘v’ [-Wunused-variable]
    float y, u, v;
          ^
../lib/igt_fb.c:1720:13: warning: unused variable ‘u’ [-Wunused-variable]
    float y, u, v;
             ^
../lib/igt_fb.c:1720:10: warning: unused variable ‘y’ [-Wunused-variable]
    float y, u, v;
                ^

Signed-off-by: Petri Latvala <petri.latvala@intel.com>
Cc: Stanislav Lisovskiy <stanislav.lisovskiy@intel.com>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Reviewed-by: Stanislav Lisovskiy <stanislav.lisovskiy@intel.com>