Allow disabling SSH

The intent behind this commit is to add the dropbear service, monitor
the Enabled and Running properties, and then update the
dropbear.socket to allow disabling/enabling SSH.

Tested:
1.
busctl introspect xyz.openbmc_project.Control.Service.Manager /xyz/openbmc_project/control/service/dropbear
 xyz.openbmc_project.Control.Service.Attributes       interface
 .Enabled                property  b    false  emits-change writable
 .Masked                 property  b    false  emits-change writable
 .Running                property  b    true   emits-change writable

 Open a new SSH connection:
 sudo ssh username@<IP>
 Successfully connected

2.
busctl set-property xyz.openbmc_project.Control.Service.Manager /xyz/openbmc_project/control/service/dropbear xyz.openbmc_project.Control.Service.Attributes Running b false

busctl introspect xyz.openbmc_project.Control.Service.Manager /xyz/openbmc_project/control/service/dropbear
 xyz.openbmc_project.Control.Service.Attributes       interface
 .Enabled                property  b    false  emits-change writable
 .Masked                 property  b    false  emits-change writable
 .Running                property  b    false  emits-change writable

 Open a new SSH connection:
 sudo ssh username@<IP>
 ssh: connect to host <IP> port 22: Connection refused

Signed-off-by: George Liu <liuxiwei@inspur.com>
Change-Id: I5d004f7f49c25fc90b93dabd124fe0d3d93ca822
diff --git a/src/main.cpp b/src/main.cpp
index f8d1f22..1d9ebed 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -34,28 +34,9 @@
 
 // Base service name list. All instance of these services and
 // units(service/socket) will be managed by this daemon.
-static std::array<std::string, 5> serviceNames = {
-    "phosphor-ipmi-net", "bmcweb", "phosphor-ipmi-kcs", "start-ipkvm",
-    "obmc-console"};
-
-using ListUnitsType =
-    std::tuple<std::string, std::string, std::string, std::string, std::string,
-               std::string, sdbusplus::message::object_path, uint32_t,
-               std::string, sdbusplus::message::object_path>;
-
-enum class ListUnitElements
-{
-    name,
-    descriptionString,
-    loadState,
-    activeState,
-    subState,
-    followedUnit,
-    objectPath,
-    queuedJobType,
-    jobType,
-    jobObject
-};
+static std::array<std::string, 6> serviceNames = {
+    "phosphor-ipmi-net", "bmcweb",       "phosphor-ipmi-kcs",
+    "start-ipkvm",       "obmc-console", "dropbear"};
 
 enum class UnitType
 {