Add option to enable/disable forced warm reboots

Some OpenBMC systems don't support a forced warm reboot. Provide a
compile option to enable/disable.

Tested:
- Confirmed that if feature is disabled, then AllowedHostTransitions did
  not have ForceWarmReboot option.

Change-Id: I207b8fa7e3f60efbf406397ff4df980a5d2677ed
Signed-off-by: Andrew Geissler <geissonator@yahoo.com>
diff --git a/host_state_manager.cpp b/host_state_manager.cpp
index bf5e79a..160872d 100644
--- a/host_state_manager.cpp
+++ b/host_state_manager.cpp
@@ -88,8 +88,14 @@
 void Host::setupSupportedTransitions()
 {
     std::set<Transition> supportedTransitions = {
-        Transition::On, Transition::Off, Transition::Reboot,
-        Transition::GracefulWarmReboot, Transition::ForceWarmReboot};
+        Transition::On,
+        Transition::Off,
+        Transition::Reboot,
+        Transition::GracefulWarmReboot,
+#if ENABLE_FORCE_WARM_REBOOT
+        Transition::ForceWarmReboot,
+#endif
+    };
     server::Host::allowedHostTransitions(supportedTransitions);
 }