drm/panel: Initialise panel dev and funcs through drm_panel_init()

Instead of requiring all drivers to set the dev and funcs fields of
drm_panel manually after calling drm_panel_init(), pass the data as
arguments to the function. This simplifies the panel drivers, and will
help future refactoring when adding new arguments to drm_panel_init().

The panel drivers have been updated with the following Coccinelle
semantic patch, with manual inspection to verify that no call to
drm_panel_init() with a single argument still exists.

@@
expression panel;
expression device;
identifier ops;
@@
 drm_panel_init(&panel
+	, device, &ops
 );
 ...
(
-panel.dev = device;
-panel.funcs = &ops;
|
-panel.funcs = &ops;
-panel.dev = device;
)

Suggested-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20190823193245.23876-3-laurent.pinchart@ideasonboard.com