drm/sun4i: tcon: Separate quirks for tcon0 and tcon1 on A20

Timing controllers on A20 are not equivalent: tcon0 on A20 supports
LVDS output and tcon1 does not. Separate the capabilities by
introducing independent set of quirks for each of the tcons.

Signed-off-by: Andrey Lebedev <andrey@lebedev.lt>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://patchwork.freedesktop.org/patch/msgid/20200219180858.4806-3-andrey.lebedev@gmail.com