Add more specific lvm2 version to PACKAGERS document

I personally tested this using our container, and this was the lowest version that compiles and runs properly.

Docker-DCO-1.0-Signed-off-by: Andrew Page <admwiggin@gmail.com> (github: tianon)
Merge pull request #3500 from tianon/lvm2-version

Add more specific lvm2 version to PACKAGERS document