Add update|hotfix repo classes

  * fluentd
  * elastic
  * Misc: fix arch. variable

Prod-related: PROD-23765 (PROD:23765)

Change-Id: If5997c29e1d12c68d4abd8a3f83b6eb21a8add99
(cherry picked from commit 715a757d13aec6757db5f2bd267840544d1156cf)
diff --git a/linux/system/repo/mcp/apt_mirantis/fluentd.yml b/linux/system/repo/mcp/apt_mirantis/fluentd.yml
index 09503a2..825b1c2 100644
--- a/linux/system/repo/mcp/apt_mirantis/fluentd.yml
+++ b/linux/system/repo/mcp/apt_mirantis/fluentd.yml
@@ -7,5 +7,5 @@
         mcp_fluentd:
           source: "deb [arch=amd64] ${_param:linux_system_repo_mcp_fluentd_url}/${_param:linux_system_codename} ${_param:linux_system_codename} contrib"
           key: ${_param:linux_system_repo_mcp_fluentd_key}
-          architectures: amd64
+          architectures: ${_param:linux_system_architecture}
           clean_file: true