[lldb] Fix printf format errors

This patch fixes:

  lldb/source/Plugins/Language/CPlusPlus/LibCxx.cpp:1108:39: error:
  format specifies type 'long long' but the argument has type
  'std::time_t' (aka 'long') [-Werror,-Wformat]

  lldb/source/Plugins/Language/CPlusPlus/LibCxx.cpp:1116:64: error:
  format specifies type 'long long' but the argument has type
  'std::time_t' (aka 'long') [-Werror,-Wformat]

Author: kazutakahirata

lldb/source/Plugins/Language/CPlusPlus/LibCxx.cpp

@@ -1105,15 +1105,16 @@ bool lldb_private::formatters::LibcxxChronoSysSecondsSummaryProvider(
 
   const std::time_t seconds = ptr_sp->GetValueAsSigned(0);
   if (seconds < chrono_timestamp_min || seconds > chrono_timestamp_max)
-    stream.Printf("timestamp=%lld s", seconds);
+    stream.Printf("timestamp=%" PRIu64 " s", static_cast<uint64_t>(seconds));
   else {
     std::array<char, 128> str;
     std::size_t size =
         std::strftime(str.data(), str.size(), "%FT%H:%M:%SZ", gmtime(&seconds));
     if (size == 0)
       return false;
 
-    stream.Printf("date/time=%s timestamp=%lld s", str.data(), seconds);
+    stream.Printf("date/time=%s timestamp=%" PRIu64 " s", str.data(),
+                  static_cast<uint64_t>(seconds));
   }
 
   return true;