MLK-16015-2 phy: mixel-lvds-combo: Add delay to wait PHY to be locked

It seems that we haven't got SCU ISO bit available to check if PHY is
locked or not after enable, so let's simply delay for a while as a
temporary solution.

Signed-off-by: Liu Ying <victor.liu@nxp.com>

drivers/phy/phy-mixel-lvds-combo.c

@@ -13,6 +13,7 @@
  */
 
 #include <linux/clk.h>
+#include <linux/delay.h>
 #include <linux/io.h>
 #include <linux/kernel.h>
 #include <linux/module.h>
@@ -174,6 +175,8 @@ static int mixel_lvds_combo_phy_power_on(struct phy *phy)
 	phy_csr_write(phy, val, PHY_CTRL);
 	mutex_unlock(&lvds_phy->lock);
 
+	usleep_range(500, 1000);
+
 	return 0;
 }