message: Fix compiler warning
  Fixes warning: comparison of integers of different signs.
diff: @@ -241,8 +241,7 @@ DynamicLoaderDarwinKernel::SearchForKernelWithDebugHints(Process *process) {
  0xffffff8000002010ULL, // oldest arm64 devices
  LLDB_INVALID_ADDRESS};
  addr_t kernel_addresses_32[] = {0xffff0110, // 2016 and earlier armv7 devices
  - 0xffff1010,
  - LLDB_INVALID_ADDRESS};
  + 0xffff1010, LLDB_INVALID_ADDRESS};
  uint8_t uval[8];
  if (process->GetAddressByteSize() == 8) {
  @@ -1245,9 +1244,9 @@ bool DynamicLoaderDarwinKernel::ParseKextSummaries(
  // If this "kext" entry is actually an alias for the kernel -- the kext was
  // compiled into the kernel or something -- then we don't want to load the
  // kernel's text section at a different address. Ignore this kext entry.
  - if (kext_summaries[new_kext].GetUUID().IsValid()
  - && m_kernel.GetUUID().IsValid()
  - && kext_summaries[new_kext].GetUUID() == m_kernel.GetUUID()) {
  + if (kext_summaries[new_kext].GetUUID().IsValid() &&
  + m_kernel.GetUUID().IsValid() &&
  + kext_summaries[new_kext].GetUUID() == m_kernel.GetUUID()) {
  to_be_added[new_kext] = false;
  break;
  }
  @@ -1301,8 +1300,7 @@ bool DynamicLoaderDarwinKernel::ParseKextSummaries(
  bool kext_successfully_added = true;
  if (load_kexts) {
  if (!image_info.LoadImageUsingMemoryModule(m_process)) {
  - kexts_failed_to_load.push_back(
  - std::pair<std::string, UUID>(
  + kexts_failed_to_load.push_back(std::pair<std::string, UUID>(
  kext_summaries[new_kext].GetName(),
  kext_summaries[new_kext].GetUUID()));
  image_info.LoadImageAtFileAddress(m_process);
  @@ -1361,7 +1359,7 @@ bool DynamicLoaderDarwinKernel::ParseKextSummaries(
  (int)kexts_failed_to_load.size(),
  number_of_new_kexts_being_added);
  // print a sorted list of <kext-name, uuid> kexts which failed to load
  - int longest_name = 0;
  + unsigned longest_name = 0;
  std::sort(kexts_failed_to_load.begin(), kexts_failed_to_load.end());
  for (const auto &ku : kexts_failed_to_load) {
  if (ku.first.size() > longest_name)
  