drm/panel: sitronix-st7789v: fix timing for jt240mhqs_hwt_ek_e3 panel

Flickering was observed when using partial mode. Moving the vsync to the
same position as used by the default sitronix-st7789v timing resolves this
issue.

Fixes: 0fbbe96 ("drm/panel: sitronix-st7789v: add jasonic jt240mhqs-hwt-ek-e3 support")
Acked-by: Jessica Zhang <quic_jesszhan@quicinc.com>
Signed-off-by: Gerald Loacker <gerald.loacker@wolfvision.net>
Link: https://lore.kernel.org/r/20240409-bugfix-jt240mhqs_hwt_ek_e3-timing-v2-1-e4821802443d@wolfvision.net
Signed-off-by: Neil Armstrong <neil.armstrong@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20240409-bugfix-jt240mhqs_hwt_ek_e3-timing-v2-1-e4821802443d@wolfvision.net

Author: Gerald08

drivers/gpu/drm/panel/panel-sitronix-st7789v.c

@@ -286,9 +286,9 @@ static const struct drm_display_mode jt240mhqs_hwt_ek_e3_mode = {
 	.hsync_end = 240 + 28 + 10,
 	.htotal = 240 + 28 + 10 + 10,
 	.vdisplay = 280,
-	.vsync_start = 280 + 8,
-	.vsync_end = 280 + 8 + 4,
-	.vtotal = 280 + 8 + 4 + 4,
+	.vsync_start = 280 + 48,
+	.vsync_end = 280 + 48 + 4,
+	.vtotal = 280 + 48 + 4 + 4,
 	.width_mm = 43,
 	.height_mm = 37,
 	.flags = DRM_MODE_FLAG_PHSYNC | DRM_MODE_FLAG_PVSYNC,