staging: vc04_services: Remove unused structs

Removes unused opaque struct typedefs. Issue found by checkpatch.

Signed-off-by: Jamal Shareef <jamal.k.shareef@gmail.com>
Link: https://lore.kernel.org/r/acc1e07a0b2c4e67ae417086087c9ce3d7f932f4.1572652827.git.jamal.k.shareef@gmail.com


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>