drm/imx: consolidate bus format variable names

This patch consolidates the different interface_pix_fmt, pixel_fmt, pix_fmt,
and pixfmt variables to a common name "bus_format" wherever they describe the
pixel format on the bus between display controller and encoder hardware.
At the same time, it renames imx_drm_panel_format to imx_drm_set_bus_format.

Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
Tested-by: Emil Renner Berthing <kernel@esmil.dk>
diff --git a/drivers/gpu/drm/imx/imx-ldb.c b/drivers/gpu/drm/imx/imx-ldb.c
index f9ec17a..cd062b1 100644
--- a/drivers/gpu/drm/imx/imx-ldb.c
+++ b/drivers/gpu/drm/imx/imx-ldb.c
@@ -163,24 +163,24 @@
 {
 	struct imx_ldb_channel *imx_ldb_ch = enc_to_imx_ldb_ch(encoder);
 	struct imx_ldb *ldb = imx_ldb_ch->ldb;
-	u32 pixel_fmt;
+	u32 bus_format;
 
 	switch (imx_ldb_ch->chno) {
 	case 0:
-		pixel_fmt = (ldb->ldb_ctrl & LDB_DATA_WIDTH_CH0_24) ?
+		bus_format = (ldb->ldb_ctrl & LDB_DATA_WIDTH_CH0_24) ?
 			MEDIA_BUS_FMT_RGB888_1X24 : MEDIA_BUS_FMT_RGB666_1X18;
 		break;
 	case 1:
-		pixel_fmt = (ldb->ldb_ctrl & LDB_DATA_WIDTH_CH1_24) ?
+		bus_format = (ldb->ldb_ctrl & LDB_DATA_WIDTH_CH1_24) ?
 			MEDIA_BUS_FMT_RGB888_1X24 : MEDIA_BUS_FMT_RGB666_1X18;
 		break;
 	default:
 		dev_err(ldb->dev, "unable to config di%d panel format\n",
 			imx_ldb_ch->chno);
-		pixel_fmt = MEDIA_BUS_FMT_RGB888_1X24;
+		bus_format = MEDIA_BUS_FMT_RGB888_1X24;
 	}
 
-	imx_drm_panel_format(encoder, pixel_fmt);
+	imx_drm_set_bus_format(encoder, bus_format);
 }
 
 static void imx_ldb_encoder_commit(struct drm_encoder *encoder)