generic: ar8216: do a software reset for switch during hw_init

This applies to ar8216 and ar8236. QCA's newer U-boot will enable
the switch mdio master for FE switches which makes phy inaccessible
from CPU mdio. (e.g. on TP-Link TL-WR941N v7 Chinese version which
uses QCA9558+AR8236.) For these devices PHY probing is broken and
mdio device probing is a must. We also need to disable switch mdio
master in driver for later PHY initialization.

Do a soft reset during hw_init so that mdio master can be disabled
and expose PHYs to CPU mdio for later PHY accessing.

Signed-off-by: Chuanhong Guo <gch981213@gmail.com>

target/linux/generic/files/drivers/net/phy/ar8216.c

@@ -705,6 +705,9 @@ ar8216_hw_init(struct ar8xxx_priv *priv)
 	if (priv->initialized)
 		return 0;
 
+	ar8xxx_write(priv, AR8216_REG_CTRL, AR8216_CTRL_RESET);
+	ar8xxx_reg_wait(priv, AR8216_REG_CTRL, AR8216_CTRL_RESET, 0, 1000);
+
 	ar8xxx_phy_init(priv);
 
 	priv->initialized = true;