phy: Constify struct phy_ops variables

The phy_ops variables are never modified after initialized in these
drivers, so make them const.

Signed-off-by: Axel Lin <axel.lin@ingics.com>
Acked-by: Patrice Chotard <patrice.chotard@st.com>
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
diff --git a/drivers/phy/phy-exynos-mipi-video.c b/drivers/phy/phy-exynos-mipi-video.c
index df7519a..2a54cab 100644
--- a/drivers/phy/phy-exynos-mipi-video.c
+++ b/drivers/phy/phy-exynos-mipi-video.c
@@ -124,7 +124,7 @@
 	return state->phys[args->args[0]].phy;
 }
 
-static struct phy_ops exynos_mipi_video_phy_ops = {
+static const struct phy_ops exynos_mipi_video_phy_ops = {
 	.power_on	= exynos_mipi_video_phy_power_on,
 	.power_off	= exynos_mipi_video_phy_power_off,
 	.owner		= THIS_MODULE,