drm/sti: Make use of the helper component_compare_of

Use the common compare helper from component.

Cc: Benjamin Gaignard <benjamin.gaignard@linaro.org>
Signed-off-by: Yong Wu <yong.wu@mediatek.com>
Link: https://lore.kernel.org/r/20220214060819.7334-12-yong.wu@mediatek.com


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>