Basically, a yoke is the shape of the pattern which is used to design some of the parts of the garment like neck or shoulders or is used around the hip to provide support. The yoke cut can be seen in the garments like a gathered skirt or body fit kurti.
The oldest use of the word seems to be the wooden bar to connect a pair of oxen used sometime before the 12th century. So maybe the "yoke" was adopted at the moment that two control devices were connected together for two pilots.