staging: tidspbridge: Remove cfg.c and cfg.h files

So far, the cfg.c file is empty, and the function prototypes in cfg.h
are not used in any place. So they can be removed.

Signed-off-by: Ivan Gomez Castellanos <ivan.gomez@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>