drm/imx: fix opencoded use of drm_panel_*

Use the drm_panel_get_modes() function to get the modes.

This patch leave one test for the function pointer:
panel->funcs->get_modes

This is used to check if the panel may have any modes.
There is no direct replacement.
We may be able to just check that drm_panel_get_modes() return > 0,
but as this is not the same functionality it is left for later.

Signed-off-by: Sam Ravnborg <[e-mail]>
Acked-by: Philipp Zabel <[e-mail]>
Reviewed-by: Emil Velikov <[e-mail]>
Cc: Shawn Guo <[e-mail]>
Cc: Sascha Hauer <[e-mail]>
Cc: Pengutronix Kernel Team <[e-mail]>
Cc: Fabio Estevam <[e-mail]>
Cc: NXP Linux Team <[e-mail]>
Cc: [e-mail]
Link: https://patchwork.freedesktop.org/patch/msgid/[e-mail]

drivers/gpu/drm/imx/imx-ldb.c

···
 static int imx_ldb_connector_get_modes(struct drm_connector *connector)
 {
 	struct imx_ldb_channel *imx_ldb_ch = con_to_imx_ldb_ch(connector);
-	int num_modes = 0;
+	int num_modes;
 
-	if (imx_ldb_ch->panel && imx_ldb_ch->panel->funcs &&
-	    imx_ldb_ch->panel->funcs->get_modes) {
-		num_modes = imx_ldb_ch->panel->funcs->get_modes(imx_ldb_ch->panel);
-		if (num_modes > 0)
-			return num_modes;
-	}
+	num_modes = drm_panel_get_modes(imx_ldb_ch->panel);
+	if (num_modes > 0)
+		return num_modes;
 
 	if (!imx_ldb_ch->edid && imx_ldb_ch->ddc)
 		imx_ldb_ch->edid = drm_get_edid(connector, imx_ldb_ch->ddc);

drivers/gpu/drm/imx/parallel-display.c

···
 {
 	struct imx_parallel_display *imxpd = con_to_imxpd(connector);
 	struct device_node *np = imxpd->dev->of_node;
-	int num_modes = 0;
+	int num_modes;
 
-	if (imxpd->panel && imxpd->panel->funcs &&
-	    imxpd->panel->funcs->get_modes) {
-		num_modes = imxpd->panel->funcs->get_modes(imxpd->panel);
-		if (num_modes > 0)
-			return num_modes;
-	}
+	num_modes = drm_panel_get_modes(imxpd->panel);
+	if (num_modes > 0)
+		return num_modes;
 
 	if (imxpd->edid) {
 		drm_connector_update_edid_property(connector, imxpd->edid);