drm: rcar-du: lvds: Fix PLL frequency-related configuration

The frequency checks don't match the datasheet, fix them.

Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
diff --git a/drivers/gpu/drm/rcar-du/rcar_du_lvdsenc.c b/drivers/gpu/drm/rcar-du/rcar_du_lvdsenc.c
index 937b2da..e044a17 100644
--- a/drivers/gpu/drm/rcar-du/rcar_du_lvdsenc.c
+++ b/drivers/gpu/drm/rcar-du/rcar_du_lvdsenc.c
@@ -56,11 +56,11 @@
 		return ret;
 
 	/* PLL clock configuration */
-	if (freq <= 38000)
+	if (freq < 39000)
 		pllcr = LVDPLLCR_CEEN | LVDPLLCR_COSEL | LVDPLLCR_PLLDLYCNT_38M;
-	else if (freq <= 60000)
+	else if (freq < 61000)
 		pllcr = LVDPLLCR_CEEN | LVDPLLCR_COSEL | LVDPLLCR_PLLDLYCNT_60M;
-	else if (freq <= 121000)
+	else if (freq < 121000)
 		pllcr = LVDPLLCR_CEEN | LVDPLLCR_COSEL | LVDPLLCR_PLLDLYCNT_121M;
 	else
 		pllcr = LVDPLLCR_PLLDLYCNT_150M;