kernel-placeholder: provide kernel modules mountpoint

It is no longer part of 'filesystem' package in Fedora 19.

rpm_spec/core-vm-kernel-placeholder.spec

@@ -24,4 +24,9 @@ Provides:   kernel-modules-extra
 %description
 Placeholder for kernel package as it is managed by Dom0.
 
+%install
+
+mkdir -p $RPM_BUILD_ROOT/lib/modules
+
 %files
+%dir /lib/modules