libs2eplugins: warning fixes

Signed-off-by: Vitaly Chipounov <vitaly@chipounov.fr>

Author: vitalych

libs2eplugins/src/s2e/Plugins/OSMonitors/Support/GuestCodeHooking.cpp

@@ -163,7 +163,7 @@ void GuestCodeHooking::erase(S2EExecutionState *state, GuestCodeHooking::GCHPred
     bool needFlush = false;
     auto eraser = [&](Hooks &hooks) {
         std::vector<HookLocation> toErase;
-        for (const auto it : hooks) {
+        for (const auto &it : hooks) {
             if (doErase(it.first, it.second)) {
                 toErase.push_back(it.first);
                 needFlush = true;

libs2eplugins/src/s2e/Plugins/VulnerabilityAnalysis/CGCInterface.cpp

@@ -350,7 +350,7 @@ bool CGCInterface::updateCoverage(S2EExecutionState *state) {
             continue;
         }
 
-        for (auto tbit : tbs) {
+        for (const auto &tbit : tbs) {
             bool covered = false;
             if (!bmp->setCovered(index, tbit.startOffset, tbit.size, covered)) {
                 success = false;