util::dbus: Make common the transition host support

Move transition host support from attention handler specific code to
common util code.

Signed-off-by: Ben Tyner <ben.tyner@ibm.com>
Change-Id: I7fb4970354aaeca65fcc074107f99262e504ac34
diff --git a/attn/vital_handler.cpp b/attn/vital_handler.cpp
index b0a771e..910c005 100644
--- a/attn/vital_handler.cpp
+++ b/attn/vital_handler.cpp
@@ -2,6 +2,7 @@
 #include <attn/attn_common.hpp>
 #include <attn/attn_logging.hpp>
 #include <sdbusplus/bus.hpp>
+#include <util/dbus.hpp>
 
 namespace attn
 {
@@ -28,7 +29,7 @@
     else
     {
         // transition host state after analyses
-        transitionHost(HostState::Quiesce);
+        util::dbus::transitionHost(util::dbus::HostState::Quiesce);
 
         // generate pel
         eventVital();