[POWERPC] Add a unified uevent handler for bus based on of_device

This common uevent handler allow the several bus types based on
of_device to generate the uevent properly and avoiding
code duplication.

This handlers take a struct device as argument and can therefore
be used as the uevent call directly if no special treatment is
needed for the bus.

Signed-off-by: Sylvain Munaut <tnt@246tNt.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
diff --git a/include/asm-powerpc/of_device.h b/include/asm-powerpc/of_device.h
index a889b20..4f1aabe 100644
--- a/include/asm-powerpc/of_device.h
+++ b/include/asm-powerpc/of_device.h
@@ -32,5 +32,8 @@
 extern void of_device_unregister(struct of_device *ofdev);
 extern void of_release_dev(struct device *dev);
 
+extern int of_device_uevent(struct device *dev,
+	char **envp, int num_envp, char *buffer, int buffer_size);
+
 #endif /* __KERNEL__ */
 #endif /* _ASM_POWERPC_OF_DEVICE_H */