staging: tidspbridge: fix compilation on dsp clock functions

Seen on v3.1-rc3, patch:

omap: mcbsp: Drop in-driver transfer support
bafe2721

Removed code that now cause tidspbridge to break while compiling.

Signed-off-by: Omar Ramirez Luna <omar.ramirez@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>