qemu: Slightly increase memory limit
qemu: Slightly increase memory limit

For low-memory domains (roughly under 400MB) our automatic memory limit
computation comes up with a limit that's too low. This is because the
0.5 multiplication does not add enough for such small values. Let's
increase the constant part of the computation to fix this.

taget/libvirt,agx/libvirt,jardasgit/libvirt,jfehlig/libvirt,olafhering/libvirt,eskultety/libvirt,rlaager/libvirt,crobinso/libvirt,shugaoye/libvirt,zhlcindy/libvirt-1.1.4-maintain,elmarco/libvirt,VenkatDatta/libvirt,fabianfreyer/libvirt,elmarco/libvirt,nertpinx/libvirt,olafhering/libvirt,agx/libvirt,jardasgit/libvirt,jardasgit/libvirt,taget/libvirt,cbosdo/libvirt,jfehlig/libvirt,shugaoye/libvirt,zippy2/libvirt,cbosdo/libvirt,rlaager/libvirt,nertpinx/libvirt,VenkatDatta/libvirt,datto/libvirt,taget/libvirt,olafhering/libvirt,eskultety/libvirt,cbosdo/libvirt,VenkatDatta/libvirt,fabianfreyer/libvirt,zhlcindy/libvirt-1.1.4-maintain,VenkatDatta/libvirt,zippy2/libvirt,olafhering/libvirt,libvirt/libvirt,taget/libvirt,libvirt/libvirt,shugaoye/libvirt,andreabolognani/libvirt,datto/libvirt,zippy2/libvirt,elmarco/libvirt,jardasgit/libvirt,cbosdo/libvirt,datto/libvirt,shugaoye/libvirt,elmarco/libvirt,nertpinx/libvirt,fabianfreyer/libvirt,libvirt/libvirt,zhlcindy/libvirt-1.1.4-maintain,rlaager/libvirt,eskultety/libvirt,jfehlig/libvirt,eskultety/libvirt,rlaager/libvirt,eskultety/libvirt,crobinso/libvirt,agx/libvirt,nertpinx/libvirt,cbosdo/libvirt,datto/libvirt,jardasgit/libvirt,VenkatDatta/libvirt,andreabolognani/libvirt,taget/libvirt,libvirt/libvirt,zhlcindy/libvirt-1.1.4-maintain,andreabolognani/libvirt,rlaager/libvirt,crobinso/libvirt,elmarco/libvirt,shugaoye/libvirt,agx/libvirt,fabianfreyer/libvirt,datto/libvirt,zhlcindy/libvirt-1.1.4-maintain,jfehlig/libvirt,crobinso/libvirt,fabianfreyer/libvirt,agx/libvirt,andreabolognani/libvirt,zippy2/libvirt,nertpinx/libvirt,andreabolognani/libvirt