LIS is included in the kernel and needs to be enabled when a kernel is compiled (which I believe Slackware does if I recall correctly). If things are running fine with your current kernel then you are good to go. If not, depending on the changelog of LIS in later kernel releases, you may need to consider if upgrading the kernel is the right choice to make. The package you linked to is for vendor specific distro and not geared to Slackware. I would not recommend an install attempt.
More info I have found:
https://docs.microsoft.com/en-us/win...r-V-on-Windows
