[libFuzzer] Use long long to ensure 64 bits.

[mpividori]

Summary

This fix errors when compiling for 64 bits on Windows, where longs are 4 bytes.

[kcc]

LGTM (with Zach's comment)

[mpividori]

@zturner Ok. I agree.

lib/Fuzzer/FuzzerTracePC.cpp

for (size_t i = 1; i < GetNumPCs(); i++) {
     std::string LineStr = DescribePC("%l", PC);
     char ModulePathRaw[4096] = "";  // What's PATH_MAX in portable C++?
     void *OffsetRaw = nullptr;
     if (!EF->__sanitizer_get_module_and_offset_for_pc(
             reinterpret_cast<void *>(PC), ModulePathRaw,
             sizeof(ModulePathRaw), &OffsetRaw))
       continue;
     std::string Module = ModulePathRaw;
-    uintptr_t FixedPC = std::stol(FixedPCStr, 0, 16);
+    uintptr_t FixedPC = std::stoll(FixedPCStr, 0, 16);
     uintptr_t PcOffset = reinterpret_cast<uintptr_t>(OffsetRaw);
     ModuleOffsets[Module] = FixedPC - PcOffset;
     CoveredPCsPerModule[Module].push_back(PcOffset);
     CoveredFunctions.insert(FunctionStr);
     CoveredFiles.insert(FileStr);
     CoveredDirs.insert(DirName(FileStr));
     if (!CoveredLines.insert(FileStr + ":" + LineStr).second)
       continue;
for (auto &M : CoveredPCsPerModule) {
     }
     std::istringstream ISS(SanCovOutput);
     std::string S;
     while (std::getline(ISS, S, '\n')) {
       size_t PcOffsetEnd = S.find(':');
       if (PcOffsetEnd == std::string::npos)
         continue;
       S.resize(PcOffsetEnd);
-      uintptr_t PcOffset = std::stol(S, 0, 16);
+      uintptr_t PcOffset = std::stoll(S, 0, 16);
       if (!std::binary_search(CoveredOffsets.begin(), CoveredOffsets.end(),
                               PcOffset)) {
         uintptr_t PC = ModuleOffset + PcOffset;
         auto FileStr = DescribePC("%s", PC);
         if (!IsInterestingCoverageFile(FileStr)) continue;
         if (CoveredFiles.count(FileStr) == 0) {
           UncoveredFiles.insert(FileStr);
           continue;