i2c: mux: create "channel-n" symlinks for child segments in the mux device
i2c: mux: create "channel-n" symlinks for child segments in the mux device

This makes the topology clearer. For instance, by adding a pca9547
device with address 0x70 to bus i2c-0, you get:

/sys/class/i2c-dev/i2c-0/device/0-0070/channel-0 -> i2c-1
...
/sys/class/i2c-dev/i2c-0/device/0-0070/channel-7 -> i2c-8

Signed-off-by: Gerlando Falauto <e26ae6cd2ee390a2335b18fb193997847c3cc510@keymile.com>
[wsa: simplified sysfs-usage and fixed format string usage]
Signed-off-by: Wolfram Sang <fd4ce474653598159cad06f3c83387a05cd53a44@the-dreams.de>
Acked-by: Martin Belanger <775ab805045b13282a59a305c99c7e638c109712@cyaninc.com>
Acked-by: Danielle Costantino <1676bca51d9e1b7993ae598e6ca769328d3fd0c5@gmail.com>

KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs