htools: switch hspace to the generic binary

This is the last patch of the binaries conversion.

As information, we now have a single binary that is approx. 5.4MiB in
size, compared to 4 binaries that were approx. 5.1-5.2MiB in size;
this will result in a smaller package and install size, and the single
compilation phase should also help.

Signed-off-by: Iustin Pop <iustin@google.com>
Reviewed-by: Guido Trotter <ultrotter@google.com>