ipmid: Change .H -> .hpp

Change-Id: Ia1ed05a533736105909717b86f16274b30d36401
Signed-off-by: Patrick Williams <patrick@stwcx.xyz>
diff --git a/groupext.cpp b/groupext.cpp
index b834f9b..92edd04 100644
--- a/groupext.cpp
+++ b/groupext.cpp
@@ -1,5 +1,5 @@
 #include "ipmid-api.h"
-#include "ipmid.H"
+#include "ipmid.hpp"
 #include <stdio.h>
 #include <stdint.h>