cputimeinstate: add missing <functional> include

Bug: 175635923
Test: m MODULES-IN-frameworks-native-libs-cputimeinstate
Change-Id: I59dd519a611458e55aeb7dad014865df5e3840c3
diff --git a/libs/cputimeinstate/fuzz/cputimeinstate_fuzzer/cputimeinstate_fuzzer.cpp b/libs/cputimeinstate/fuzz/cputimeinstate_fuzzer/cputimeinstate_fuzzer.cpp
index f835997..9df5632 100644
--- a/libs/cputimeinstate/fuzz/cputimeinstate_fuzzer/cputimeinstate_fuzzer.cpp
+++ b/libs/cputimeinstate/fuzz/cputimeinstate_fuzzer/cputimeinstate_fuzzer.cpp
@@ -20,6 +20,7 @@
 #include <fuzzer/FuzzedDataProvider.h>
 #include <android-base/unique_fd.h>
 #include <cputimeinstate.h>
+#include <functional>
 
 using namespace android::bpf;