net: dsa: microchip: move interrupt handling logic from lan937x to ksz_common

To support the phy link detection through interrupt method for ksz9477
based switch, the interrupt handling routines are moved from
lan937x_main.c to ksz_common.c. The only changes made are functions
names are prefixed with ksz_ instead of lan937x_.
Signed-off-by: Arun Ramadoss <arun.ramadoss@microchip.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

drivers/net/dsa/microchip/ksz_common.h

@@ -573,6 +573,15 @@ static inline int is_lan937x(struct ksz_device *dev)
 #define P_MII_MAC_MODE			BIT(2)
 #define P_MII_SEL_M			0x3
 
+/* Interrupt */
+#define REG_SW_PORT_INT_STATUS__4	0x0018
+#define REG_SW_PORT_INT_MASK__4		0x001C
+
+#define REG_PORT_INT_STATUS		0x001B
+#define REG_PORT_INT_MASK		0x001F
+
+#define PORT_SRC_PHY_INT		1
+
 /* Regmap tables generation */
 #define KSZ_SPI_OP_RD		3
 #define KSZ_SPI_OP_WR		2