quantile.cu .. no defined equality operator for the Entry struct in the WQSummary class

[bcourtney]

error : no operator "==" matches these operands operand types are: const xgboost::common::WQSummary<float, float>::Entry == const xgboost::common::WQSummary<float, float>::Entry

[rendezvoush]

It's real, under xgboost, in the file "src/common/quantile.h", inside the template struct WQSummary, "struct Entry" has not defined the "operator=="