Remove libvirt-bin and qemu-kvm from mandatory requirements

nova-compute package already provides needed requirements, furhermore
both qemu and libvirt are completely optional and shouldn't be installed
for some nova computes like ironic or vmware.

Change-Id: I4a5eaa23c79263e4637d2802651987b72b29569e
diff --git a/nova/map.jinja b/nova/map.jinja
index 7e0006f..b929b88 100644
--- a/nova/map.jinja
+++ b/nova/map.jinja
@@ -179,9 +179,7 @@
   - pm-utils
   - sysfsutils
   - sg3-utils
-  - libvirt-bin
   - python-memcache
-  - qemu-kvm
   - python-guestfs
   - gettext-base
   services: