yum-minimal: install fedora-release-cloud

Something (possibly [1], but that change is at best cryptic) has
changed such that we don't get correct /etc/os-release files
installed.  This flows on to grub half-installing itself, enough to
not fail the build but not enough to make something bootable.

Installing the -cloud release package gets it back, and seems like a
sane choice for dib.

[1] 617b1bed34

Change-Id: Iff0413887fad798273b2bfcb140cc07f36d54a04

diskimage_builder/elements/yum-minimal/root.d/08-yum-chroot

@@ -74,7 +74,7 @@ function _install_repos {
     packages="basesystem filesystem setup "
 
     if [[ ${DISTRO_NAME} = fedora && ${DIB_RELEASE} -gt 29 ]]; then
-        packages+="${DISTRO_NAME}-release-common "
+        packages+="fedora-release-cloud fedora-release-common "
     else
         packages+="${DISTRO_NAME}-release "
     fi