FROMLIST: net: phy: qcom: qca808x: Add .get_rate_matching support

Add support for rate matching to the QCA8081 PHY driver to correctly
report its capabilities. Some boards[0][1] with this PHY currently
report support only for 2.5G.

Implement the .get_rate_matching callback to allow phylink to determine
the actual PHY capabilities and report them accurately.

Before:
 # ethtool eth0
  Settings for eth0:
         Supported ports: [  ]
         Supported link modes:   2500baseT/Full
         Supported pause frame use: Symmetric Receive-only
         ...

After:
 # ethtool eth0
  Settings for eth0:
         Supported ports: [  ]
         Supported link modes:   10baseT/Half 10baseT/Full
                                 100baseT/Half 100baseT/Full
                                 1000baseT/Full
                                 2500baseT/Full
         Supported pause frame use: Symmetric Receive-only
         ...

[0] https://lore.kernel.org/all/20250905192350.1223812-3-umang.chheda@oss.qualcomm.com/
[1] https://lore.kernel.org/all/20250908-lemans-evk-bu-v4-12-5c319c696a7d@oss.qualcomm.com/

(cherry picked from commit d02d173)
Link: https://lore.kernel.org/netdev/20250914-qca808x_rate_match-v1-1-0f9e6a331c3b@oss.qualcomm.com/
Signed-off-by: Mohd Ayaan Anwar <mohd.anwar@oss.qualcomm.com>

Author: ayaan-anwar

drivers/net/phy/qcom/qca808x.c

@@ -643,6 +643,15 @@ static void qca808x_get_phy_stats(struct phy_device *phydev,
 	qcom_phy_get_stats(stats, priv->hw_stats);
 }
 
+static int qca808x_get_rate_matching(struct phy_device *phydev,
+				     phy_interface_t iface)
+{
+	if (iface == PHY_INTERFACE_MODE_2500BASEX)
+		return RATE_MATCH_PAUSE;
+
+	return RATE_MATCH_NONE;
+}
+
 static struct phy_driver qca808x_driver[] = {
 {
 	/* Qualcomm QCA8081 */
@@ -674,6 +683,7 @@ static struct phy_driver qca808x_driver[] = {
 	.led_polarity_set	= qca808x_led_polarity_set,
 	.update_stats		= qca808x_update_stats,
 	.get_phy_stats		= qca808x_get_phy_stats,
+	.get_rate_matching      = qca808x_get_rate_matching,
 }, };
 
 module_phy_driver(qca808x_driver);