Fix compilation on sparc with gcc 4.9

src/libumockdev-preload.c:964:4: error: format '%li' expects argument of type 'long int', but argument 4 has type '__suseconds_t' [-Werror=format=]
    e->time.tv_sec, e->time.tv_usec, e->type, e->code, e->value);
Fix ioctl-tree.c warnings

Comment out ioctl-tree.c functions for variable length structs, as there are
currently no defined ioctls which use those.