cbus: Fix compile by converting ioctl calls to unlocked_ioctlcalls

Locked .ioctl is gone from struct file_operations by commit b19dd42
so these cbus drivers don't compile. Also it seems there is no need for BKL
anyway in these drivers.

Signed-off-by: Jarkko Nikula <jhnikula@gmail.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>