test scripts: add rpm-build package in vm_setup.sh

This package is needed in vm_setup.sh for vpp,
without this will report "rpmbuild: command not found".

Signed-off-by: yidong0635 <dongx.yi@intel.com>
Change-Id: Ic00a55addc940e359aae17b45e58b9a736b08fd3
Reviewed-on: https://review.gerrithub.io/c/spdk/spdk/+/447282


Tested-by: SPDK CI Jenkins <sys_sgci@intel.com>
Reviewed-by: Piotr Pelpliński <piotr.pelplinski@intel.com>
Reviewed-by: Jim Harris <james.r.harris@intel.com>
Reviewed-by: Darek Stojaczyk <dariusz.stojaczyk@intel.com>