Change apt_mk_version => mcp_version

   * Alligh all variables to one
   * Due mcp_version: ${_param:apt_mk_version}
     those change still bw compatible

Bug-relateted: PROD-24789 (PROD:24789)
Change-Id: I30b6fb0b1cb66c7d56dbb3a5e15c8bc9606405b5
diff --git a/linux/system/repo/mcp/apt_mirantis/ceph.yml b/linux/system/repo/mcp/apt_mirantis/ceph.yml
index 12011ac..6c578a9 100644
--- a/linux/system/repo/mcp/apt_mirantis/ceph.yml
+++ b/linux/system/repo/mcp/apt_mirantis/ceph.yml
@@ -16,7 +16,7 @@
 # Deprecated since 2018.11+
 #parameters:
 #  _param:
-#    linux_system_repo_mcp_ceph_version: ${_param:apt_mk_version}
+#    linux_system_repo_mcp_ceph_version: ${_param:mcp_version}
 #    linux_system_repo_mcp_ceph_codename: luminous
 #  linux:
 #    system: