net: phy: Move is_rgmii helper to phy.h

Move the phy_interface_is_rgmii to the phy.h
file for all phy's to be able to use the API.

This now aligns with the Linux kernel based on
commit e463d88c36d42211aa72ed76d32fb8bf37820ef1

Signed-off-by: Dan Murphy <dmurphy@ti.com>
Reviewed-by: Mugunthan V N <mugunthanvnm@ti.com>
Reviewed-by: Michal Simek <michal.simek@xilinx.com>
Tested-by: Mugunthan V N <mugunthanvnm@ti.com>
Acked-by: Joe Hershberger <joe.hershberger@ni.com>
diff --git a/drivers/net/phy/ti.c b/drivers/net/phy/ti.c
index 4c4f0c1..4c19353 100644
--- a/drivers/net/phy/ti.c
+++ b/drivers/net/phy/ti.c
@@ -156,17 +156,6 @@
 	phy_write(phydev, addr, MII_MMD_DATA, data);
 }
 
-/**
- * phy_interface_is_rgmii - Convenience function for testing if a PHY interface
- * is RGMII (all variants)
- * @phydev: the phy_device struct
- */
-static inline bool phy_interface_is_rgmii(struct phy_device *phydev)
-{
-	return phydev->interface >= PHY_INTERFACE_MODE_RGMII &&
-		phydev->interface <= PHY_INTERFACE_MODE_RGMII_TXID;
-}
-
 #if defined(CONFIG_DM_ETH)
 /**
  * dp83867_data_init - Convenience function for setting PHY specific data
diff --git a/include/phy.h b/include/phy.h
index 969992c..7346da7 100644
--- a/include/phy.h
+++ b/include/phy.h
@@ -278,6 +278,17 @@
  */
 int phy_get_interface_by_name(const char *str);
 
+/**
+ * phy_interface_is_rgmii - Convenience function for testing if a PHY interface
+ * is RGMII (all variants)
+ * @phydev: the phy_device struct
+ */
+static inline bool phy_interface_is_rgmii(struct phy_device *phydev)
+{
+	return phydev->interface >= PHY_INTERFACE_MODE_RGMII &&
+		phydev->interface <= PHY_INTERFACE_MODE_RGMII_TXID;
+}
+
 /* PHY UIDs for various PHYs that are referenced in external code */
 #define PHY_UID_CS4340  0x13e51002
 #define PHY_UID_TN2020	0x00a19410