(RAZOR-145) Add dmidecode (and virt-what) to microkernel

Without this patch the microkernel 004 release includes `dmidecode`, but the
build automation tools do not explicitly express a dependency on dmidecode.
This is a problem because it is not clear there is a requirement to always
include `dmidecode` in the microkernel.  If this requirement is not met for
some reason in the future key facts may be omitted.

This patch addresses the problem by explicitly adding dmidecode to the
kickstart configuration for the microkernel in an effort to ensure the
executable is always present for use with facter.

In addition, virt-what is added since this tool helps provide more accurate
virtualization fact support and so this dependency is explicitly listed in the
kickstart configuration.