baro: Make the read code work with the latest TWI frame format.
twi: Stop treating the sub value as write data.

This creates too much overhead for requests.
Revert "twi: Stop treating the sub value as write data."

This reverts commit 3b1c21cd857562fefac378eb7466ee4d5848fa3d.

Apparently this doesn't work with some devices...
Revert "baro: Make the read code work with the latest TWI frame format."

This reverts commit e5b55a752448e1bb3d705b142941f9892ff7af06.