This commit removes the functions criu_(local_)set_service_comm().
These functions are not neccessary, because if
set_service_address(), set_service_fd() or
set_service_binary() has been called it is already clear, which
service comm type should be used.

Furhtermore, this commit reduces the number of misuses.
E.g. if set_service_comm() was set to socket, but a binary was given
via set_service_binary().
Signed-off-by: Martin Wührer <martin.wuehrer@artech.at>