staging: tidspbridge: remove driver

The driver has been broken and disabled for several kernel versions now.
It doesn't have a maintainer anymore, and most of the people who've
worked on it have moved on. There's also still a long list of issues in
the TODO file before it can be moved out of staging. Until someone can
put in the work to make the driver work again and move it out of
staging, remove it from the kernel.

Signed-off-by: Kristina Martšenko <kristina.martsenko@gmail.com>
Cc: Omar Ramirez Luna <omar.ramirez@copitl.com>
Cc: Suman Anna <s-anna@ti.com>
Cc: Felipe Contreras <felipe.contreras@gmail.com>
Cc: Ohad Ben-Cohen <ohad@wizery.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>