device: Export enable_static_device() function

The work done by enable_static_devices() and scan_generic_bus()
is common and can be used by other device handlers to enable a
single static device.

Signed-off-by: Duncan Laurie <dlaurie@google.com>
Change-Id: Ibfde9c4eb794714ebd9800e52b91169ceba15266
Reviewed-on: https://review.coreboot.org/c/coreboot/+/46541
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Furquan Shaikh <furquan@google.com>

src/include/device/device.h

@@ -358,6 +358,7 @@ static inline DEVTREE_CONST void *config_of_soc(void)
 	return config_of(pcidev_on_root(0, 0));
 }
 
+void enable_static_device(struct device *dev);
 void enable_static_devices(struct device *bus);
 void scan_smbus(struct device *bus);
 void scan_generic_bus(struct device *bus);