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/meson.build b/meson.build
index cd01c3a..55f9b47 100644
--- a/meson.build
+++ b/meson.build
@@ -89,6 +89,10 @@
     add_project_arguments('-DENABLE_WARM_REBOOT',language:'cpp')
 endif
 
+if(get_option('force-warm-reboot').allowed())
+    add_project_arguments('-DENABLE_FORCE_WARM_REBOOT',language:'cpp')
+endif
+
 nlohmann_json_dep = dependency('nlohmann_json', include_type: 'system')
 sdbusplus = dependency('sdbusplus')
 sdeventplus = dependency('sdeventplus')