Revert "dom0/spec: fix HVM settings on upgrade"
Revert "dom0/spec: fix HVM settings on upgrade"

This reverts commit 4b44f977db3044396cd1b9e569100af1da9af767.
This doesn't actually fix the problem, because in %post new qubes.py is already
installed and maxmem=memory is no longer true.

marmarek/qubes-core-admin,woju/qubes-core-admin,woju/qubes-core-admin,woju/qubes-core-admin,QubesOS/qubes-core-admin,QubesOS/qubes-core-admin,marmarek/qubes-core-admin,woju/qubes-core-admin,marmarek/qubes-core-admin,QubesOS/qubes-core-admin