Fix for failure of sending signal

Redfish events are not generated even though sensor
crossed threshold value.

So changed the check for is_initialized() in the
new_signal.

Tested:
Verified and able to see RedFish event logs,
when sensor crossed threshold values.

Change-Id: I25b0340de4538b35db9be7a257fa856f2a6f2bb8
Signed-off-by: Jitendra Tripathy <jitendra.kumarx.tripathy@intel.com>
diff --git a/include/sdbusplus/asio/object_server.hpp b/include/sdbusplus/asio/object_server.hpp
index 5a02f92..6123bd4 100644
--- a/include/sdbusplus/asio/object_server.hpp
+++ b/include/sdbusplus/asio/object_server.hpp
@@ -711,7 +711,7 @@
      */
     auto new_signal(const char* member)
     {
-        if (is_initialized())
+        if (!is_initialized())
         {
             return message_t(nullptr);
         }