drm/i2c/ch7006: Don't use POWER_LEVEL_FULL_POWER_OFF on early chip versions.

Signed-off-by: Francisco Jerez <currojerez@riseup.net>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
diff --git a/drivers/gpu/drm/i2c/ch7006_drv.c b/drivers/gpu/drm/i2c/ch7006_drv.c
index 833b35f..08792a7 100644
--- a/drivers/gpu/drm/i2c/ch7006_drv.c
+++ b/drivers/gpu/drm/i2c/ch7006_drv.c
@@ -470,6 +470,7 @@
 	priv->hmargin = 50;
 	priv->vmargin = 50;
 	priv->last_dpms = -1;
+	priv->chip_version = ch7006_read(client, CH7006_VERSION_ID);
 
 	if (ch7006_tv_norm) {
 		for (i = 0; i < NUM_TV_NORMS; i++) {