device/smbus: Drop unused smbus_set_link()

I expect it to be easier to just remodel the support for i2c
multiplexers instead. Besides, there was no proper bounds for
pbus_num when accessing pbus_a[].

Change-Id: I17f33b308c01e48bc03b142550535c32862442ac
Signed-off-by: Kyösti Mälkki <kyosti.malkki@gmail.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/38161
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net>
Reviewed-by: Nico Huber <nico.h@gmx.de>

src/include/device/device.h

@@ -41,7 +41,6 @@ struct device_operations {
 	void (*scan_bus)(struct device *bus);
 	void (*enable)(struct device *dev);
 	void (*disable)(struct device *dev);
-	void (*set_link)(struct device *dev, unsigned int link);
 	void (*reset_bus)(struct bus *bus);
 #if CONFIG(GENERATE_SMBIOS_TABLES)
 	int (*get_smbios_data)(struct device *dev, int *handle,

src/include/device/smbus.h

@@ -28,7 +28,6 @@ static inline const struct smbus_bus_operations *ops_smbus_bus(struct bus *bus)
 }
 
 struct bus *get_pbus_smbus(struct device *dev);
-int smbus_set_link(struct device *dev);
 
 static inline int smbus_recv_byte(struct device *const dev)
 {