bitbake: data: Drop deprecated old style bitbake API

bitbake: data: Drop deprecated old style bitbake API

The old style bb.data.getVar/setVar API has long since been deprecated in
favour of d.getVar/setVar and friends.

Now we're about to change the default expansion parameter, drop the old APIs
to simplify the transition and ensure everyone is using the new style functions.
Conversion is trivial if there are remaining stragglers.

I've left bb.data.expand() for now since its more widely used but would make a good
follow up patch series.

(Bitbake rev: 1825604d46fcd29fad6cfd325f1cb1e1b457d2c9)

Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>