stop installing manager header

Stop installing the manager header as it is no longer meant to be
exported, but rather used only internally within this repository.

Change-Id: I2ab21a31fd745e1b3e36fc39ffea5e26d373ff51
Signed-off-by: Patrick Venture <venture@google.com>
diff --git a/utils.cpp b/utils.cpp
index 24166ca..e03ec90 100644
--- a/utils.cpp
+++ b/utils.cpp
@@ -17,10 +17,10 @@
 #include "utils.hpp"
 
 #include "fs.hpp"
+#include "manager.hpp"
 
 #include <dlfcn.h>
 
-#include <blobs-ipmid/manager.hpp>
 #include <memory>
 #include <phosphor-logging/log.hpp>
 #include <regex>