video: dw_mipi_dsi: Fix hsync/vsync settings

These must be read from timings->flags, like other DSI HOST drivers do.

And they must not be inverted either. Low means low.

Without this fix, panel drivers that set *SYNC_LOW produce corrupted
output on screen (shifted horizontally and vertically by back porch
distance).

Signed-off-by: Ondrej Jirman <megi@xff.cz>
diff --git a/drivers/video/dw_mipi_dsi.c b/drivers/video/dw_mipi_dsi.c
index 92e388a..22fef7e 100644
--- a/drivers/video/dw_mipi_dsi.c
+++ b/drivers/video/dw_mipi_dsi.c
@@ -538,9 +538,9 @@
 		break;
 	}
 
-	if (device->mode_flags & DISPLAY_FLAGS_VSYNC_HIGH)
+	if (timings->flags & DISPLAY_FLAGS_VSYNC_LOW)
 		val |= VSYNC_ACTIVE_LOW;
-	if (device->mode_flags & DISPLAY_FLAGS_HSYNC_HIGH)
+	if (timings->flags & DISPLAY_FLAGS_HSYNC_LOW)
 		val |= HSYNC_ACTIVE_LOW;
 
 	dsi_write(dsi, DSI_DPI_VCID, DPI_VCID(dsi->channel));