drm/sun4i: Add basic support for DE3

Display Engine 3 is an upgrade of DE2 with new features like support for
10 bit color formats and support for AFBC.

Most of DE2 code works with DE3, except some small details.

Implement basic support for DE3. Support for 10 bit colort formats and
AFBC, among others missing features, will be added later.

Signed-off-by: Jernej Skrabec <jernej.skrabec@siol.net>
Signed-off-by: Maxime Ripard <maxime.ripard@bootlin.com>
Link: https://patchwork.freedesktop.org/patch/260238/

drm/sun4i: Rework DE2 register defines

Most, if not all, registers found in DE2 still exists in DE3. However,
units are on different base addresses.

To prepare for addition of DE3 support, registers macros are reworked so
they take base address as parameter.

Signed-off-by: Jernej Skrabec <jernej.skrabec@siol.net>
[rebased]
Signed-off-by: Icenowy Zheng <icenowy@aosc.io>
Signed-off-by: Maxime Ripard <maxime.ripard@bootlin.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20181104182705.18047-10-jernej.skrabec@siol.net

drm/sun4i: Add support for HW scaling to DE2

Scaling is currently supported only for RGB framebuffers

Coefficients and algorithm which coefficients to select are taken
from BSP driver.

Signed-off-by: Jernej Skrabec <jernej.skrabec@siol.net>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171201060550.10392-22-jernej.skrabec@siol.net