Logging: add event for clearing

The phosphor-logging had an internal event reported for when the event
log is cleared.  Create an equivalent event here for better
documentation (and using the new event format).

Signed-off-by: Patrick Williams <patrick@stwcx.xyz>
Change-Id: Ia8e0e329c5a2818376f0fb313531a1040af23dd6
diff --git a/gen/xyz/openbmc_project/Logging/meson.build b/gen/xyz/openbmc_project/Logging/meson.build
index 3fbbcbb..39baab1 100644
--- a/gen/xyz/openbmc_project/Logging/meson.build
+++ b/gen/xyz/openbmc_project/Logging/meson.build
@@ -1,4 +1,18 @@
 # Generated file; do not modify.
+generated_sources += custom_target(
+    'xyz/openbmc_project/Logging__cpp'.underscorify(),
+    input: [ '../../../../yaml/xyz/openbmc_project/Logging.events.yaml',  ],
+    output: [ 'event.cpp', 'event.hpp',  ],
+    depend_files: sdbusplusplus_depfiles,
+    command: [
+        sdbuspp_gen_meson_prog, '--command', 'cpp',
+        '--output', meson.current_build_dir(),
+        '--tool', sdbusplusplus_prog,
+        '--directory', meson.current_source_dir() / '../../../../yaml',
+        'xyz/openbmc_project/Logging',
+    ],
+)
+
 subdir('Create')
 generated_others += custom_target(
     'xyz/openbmc_project/Logging/Create__markdown'.underscorify(),