Add power_state implementation

Added power_state implementation for multi host platform
specific shutdown interfaces like hard shutdown or soft
shutdown interfaces.

Getting the current host state of all the hosts and set
power_state values based on the hosts current host state.

TESTED : Verified the Shutdown alarms trigged and platform
specific actions done in Facebook YosemiteV2 platform.

Signed-off-by: Kumar Thangavel <thangavel.k@hcl.com>
Change-Id: I5e38bb9f28b7840c9de10082905b31deb8ffc4ff
diff --git a/configure.ac b/configure.ac
index 2cc5221..f2be82d 100644
--- a/configure.ac
+++ b/configure.ac
@@ -97,6 +97,21 @@
 AM_CONDITIONAL([WANT_MONITOR], [test "x$enable_monitor" != "xno"])
 AM_CONDITIONAL([WANT_SENSOR_MONITOR], [test "x$enable_sensor_monitor" == "xyes"])
 
+
+AC_ARG_ENABLE([host-state],
+    AS_HELP_STRING([--enable-host-state], [Enable host state]))
+
+AM_CONDITIONAL([WANT_HOST_STATE], [test "x$enable_host_state" == "xyes"])
+
+AM_COND_IF([WANT_HOST_STATE],
+    [
+        AM_CONDITIONAL(HOST_STATE_ENABLED, true)
+    ],
+    [
+        AM_CONDITIONAL(HOST_STATE_ENABLED, false)
+    ]
+)
+
 # Package specific checks.
 AS_IF([test "x$enable_presence" != "xno"], [
     # Use runtime(json) config, otherwise default to compile time(yaml) config