Only install this module on rhel, not fedora buildvm's

tasks/koji/builder_kernel_config.yml

@@ -8,3 +8,4 @@
   action: yum state=installed pkg=$item
   with_items:
   - kmod-hfsplus    
+  when: is_rhel

vars/Fedora.yml

@@ -3,4 +3,4 @@ dist_tag: f${ansible_distribution_version}
 base_pkgs_inst: ['iptables-services' ]
 base_pkgs_erase: ['firewalld', 'PackageKit*', 'sendmail', 'at']
 service_disabled: [ ]
-service_enabled: [ ]
+service_enabled: [ ]