drm/fourcc: Add format info helpers for checking YUV planes disposition

It is often useful to check whether the DRM format info retrieved from
the DRM framebuffer matches a specific YUV planes disposition.

This introduces helpers to quickly check that a provided format info
matches a YUV format with a specific disposition, in commonly-used
terminology.

The intent of providing helpers taking the format info instead of the
fourcc alone is to avoid the overhead of iterating through all formats
when the whole format info structure is available. As a result, these
helpers are very simple so they are made inline.

Signed-off-by: Paul Kocialkowski <paul.kocialkowski@bootlin.com>
Reviewed-by: Maxime Ripard <maxime.ripard@bootlin.com>
Signed-off-by: Maxime Ripard <maxime.ripard@bootlin.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190118145133.21281-2-paul.kocialkowski@bootlin.com