net: phy: aquantia: clear PMD Global Transmit Disable bit during init

PMD Global Transmit Disable bit should be cleared for normal operation.
This should be HW default, however I found that on Asus RT-AX89X that uses
AQR113C PHY and firmware 5.4 this bit is set by default.

With this bit set the AQR cannot achieve a link with its link-partner and
it took me multiple hours of digging through the vendor GPL source to find
this out, so lets always clear this bit during .config_init() to avoid a
situation like this in the future.
Signed-off-by: Robert Marko <robimarko@gmail.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Link: https://lore.kernel.org/r/20240211181732.646311-1-robimarko@gmail.comSigned-off-by: Paolo Abeni <pabeni@redhat.com>

drivers/net/phy/aquantia/aquantia_main.c

@@ -727,6 +727,15 @@ static int aqr113c_config_init(struct phy_device *phydev)
 	if (ret < 0)
 		return ret;
 
+	ret = phy_clear_bits_mmd(phydev, MDIO_MMD_PMAPMD, MDIO_PMA_TXDIS,
+				 MDIO_PMD_TXDIS_GLOBAL);
+	if (ret)
+		return ret;
+
+	ret = aqr107_wait_processor_intensive_op(phydev);
+	if (ret)
+		return ret;
+
 	return aqr107_fill_interface_modes(phydev);
 }