drm/solomon: Set preferred color depth and bpp to the correct values

Set the preferred color depth to 24 bits and the fbdev bpp to 32
bits. This will signal XRGB8888 as default format to clients.
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20221123115348.2521-7-tzimmermann@suse.de

drivers/gpu/drm/solomon/ssd130x.c

@@ -876,7 +876,7 @@ static int ssd130x_init_modeset(struct ssd130x_device *ssd130x)
 	drm->mode_config.max_width = max_width;
 	drm->mode_config.min_height = mode->vdisplay;
 	drm->mode_config.max_height = max_height;
-	drm->mode_config.preferred_depth = 32;
+	drm->mode_config.preferred_depth = 24;
 	drm->mode_config.funcs = &ssd130x_mode_config_funcs;
 
 	/* Primary plane */
@@ -1006,7 +1006,7 @@ struct ssd130x_device *ssd130x_probe(struct device *dev, struct regmap *regmap)
 	if (ret)
 		return ERR_PTR(dev_err_probe(dev, ret, "DRM device register failed\n"));
 
-	drm_fbdev_generic_setup(drm, 0);
+	drm_fbdev_generic_setup(drm, 32);
 
 	return ssd130x;
 }