Add obmc-console-ssh (SOL over SSH) support

This patch adds obmc-console-ssh service support. Like dropbear, it is
also a socket-activated service.

Tested:
1. Changing obmc-console-ssh service status and its port number works.
2. When disabling obmc-console-ssh, all active SOL SSH connections will
   be terminated in a few seconds.
3. All operations on obmc-console-ssh service will not affect dropbear
   service, and vice versa.

Change-Id: Ibf56967236a08cb34535c175e0dc5eea7fc4c84c
Signed-off-by: Jiaqing Zhao <jiaqing.zhao@intel.com>
diff --git a/src/main.cpp b/src/main.cpp
index 8e7a8a7..356095f 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -40,7 +40,8 @@
                           bool /* isSocketActivated */>
     managedServices = {{"phosphor-ipmi-net", false}, {"bmcweb", false},
                        {"phosphor-ipmi-kcs", false}, {"start-ipkvm", false},
-                       {"obmc-console", false},      {"dropbear", true}};
+                       {"obmc-console", false},      {"dropbear", true},
+                       {"obmc-console-ssh", true}};
 
 enum class UnitType
 {