Comment 17 for bug 1838245

For me, the fix is to change line 812 of /usr/sbin/dkms from:

    [ -z $kernels_module ] || return 0

to

    [ -z $kernels_module ] && return 0

This was fixed upstream here:

https://github.com/dell/dkms/commit/b95779938805aca8e98d57492b18dee07d35d285