lib/igt_draw: use igt_drm_format_to_bpp()
lib/igt_draw: use igt_drm_format_to_bpp()

Don't reimplement the function.

Acked-by: Daniel Vetter <c1b6782c4af8f0673da8923a0702a1832e5940f4@ffwll.ch>
Signed-off-by: Paulo Zanoni <cc0e04a2103c45cd195651d976f79813d0f66bdf@intel.com>

tiagovignatti/intel-gpu-tools,tiagovignatti/intel-gpu-tools,tiagovignatti/intel-gpu-tools,tiagovignatti/intel-gpu-tools