commit 6b66a6f2 upstream.

The rename did the wrong thing for this documentation file all those
years ago. Fix that as well as the neglected rename of the platform
data structure.

Fixes: e7065e20 ("i2c: Rename last mux driver to standard pattern")
Signed-off-by: Peter Rosin <peda@axentia.se>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>