clang-tidy: Cleanup headers in ipmi_handler

Add/Remove headers used in the ipmi_handler and unit test.

Change-Id: I1c2e53723e6bb43690c207039587d7c86f6fb62e
Signed-off-by: Willy Tu <wltu@google.com>
diff --git a/src/ipmiblob/ipmi_handler.cpp b/src/ipmiblob/ipmi_handler.cpp
index 3ce5d92..dd53af5 100644
--- a/src/ipmiblob/ipmi_handler.cpp
+++ b/src/ipmiblob/ipmi_handler.cpp
@@ -27,7 +27,6 @@
 #include <atomic>
 #include <cstdint>
 #include <cstring>
-#include <functional>
 #include <memory>
 #include <mutex>
 #include <sstream>
diff --git a/test/tools_ipmi_unittest.cpp b/test/tools_ipmi_unittest.cpp
index 3890bc8..bee23a6 100644
--- a/test/tools_ipmi_unittest.cpp
+++ b/test/tools_ipmi_unittest.cpp
@@ -7,8 +7,15 @@
 #include <ipmiblob/ipmi_handler.hpp>
 
 #include <chrono>
+#include <cstdint>
 #include <cstring>
+#include <memory>
+#include <string_view>
 #include <thread>
+#include <vector>
+
+#include <gmock/gmock-more-actions.h>
+#include <gtest/gtest.h>
 
 namespace ipmiblob
 {