Fix wssshtools Debian package build - missing directory creation

- Added mkdir commands to create necessary directories before install
- Fixed 'No such file or directory' error in debian/rules
- Created directories: /etc/init.d, /usr/share/wsssh, /etc/default, /usr/bin
- Ensures proper directory structure for package installation
- Resolves build failure when running build.sh --debian-only
- Maintains compatibility with existing build process