netkvm: Simplify NetKVM-VS2015.vcxproj
netkvm: Simplify NetKVM-VS2015.vcxproj

This patch removes duplicated PreBuildEvents and PostBuildEvents
from NetKVM-VS2015.vcxproj by utilizing properties defined in
Driver.Common.props. The side-effect of these changes is the new
binary drop path for Vista. Used to be Install\Vista, now
Install\Wlh like the rest of the virtio-win drivers.

YanVugenfirer/virtio-win-arm,virtio-win/kvm-guest-drivers-windows,vrozenfe/kvm-guest-drivers-windows,daynix/kvm-guest-drivers-windows,daynix/kvm-guest-drivers-windows,vrozenfe/kvm-guest-drivers-windows,daynix/kvm-guest-drivers-windows,ladipro/kvm-guest-drivers-windows,ladipro/kvm-guest-drivers-windows,YanVugenfirer/virtio-win-arm,gnif/kvm-guest-drivers-windows,YanVugenfirer/kvm-guest-drivers-windows,ladipro/kvm-guest-drivers-windows,vrozenfe/kvm-guest-drivers-windows,YanVugenfirer/virtio-win-arm,YanVugenfirer/virtio-win-arm,gnif/kvm-guest-drivers-windows,YanVugenfirer/kvm-guest-drivers-windows,vrozenfe/kvm-guest-drivers-windows,virtio-win/kvm-guest-drivers-windows,daynix/kvm-guest-drivers-windows,gnif/kvm-guest-drivers-windows,gnif/kvm-guest-drivers-windows,ladipro/kvm-guest-drivers-windows,daynix/kvm-guest-drivers-windows,virtio-win/kvm-guest-drivers-windows,YanVugenfirer/kvm-guest-drivers-windows,YanVugenfirer/kvm-guest-drivers-windows,vrozenfe/kvm-guest-drivers-windows,YanVugenfirer/kvm-guest-drivers-windows,virtio-win/kvm-guest-drivers-windows,virtio-win/kvm-guest-drivers-windows