writefrudata: drop unused sd-bus.h

Drop unused sd-bus.h header.

Change-Id: I0a55cd3aa5a551d7fa04706d7e0c5b6b275efcf5
Signed-off-by: Patrick Venture <venture@google.com>
diff --git a/writefrudata.cpp b/writefrudata.cpp
index f00c067..d9de3fe 100644
--- a/writefrudata.cpp
+++ b/writefrudata.cpp
@@ -5,7 +5,6 @@
 #include "types.hpp"
 
 #include <host-ipmid/ipmid-api.h>
-#include <systemd/sd-bus.h>
 #include <unistd.h>
 
 #include <algorithm>