Fix mismerge

Signed-off-by: Richard Chapman <rchapman@hpccsystems.com>

system/jlib/jstats.cpp

@@ -1881,6 +1881,8 @@ CNestedRuntimeStatisticMap & CRuntimeStatisticCollection::ensureNested()
     return *querySingleton(nested, nestlock, [this]{ return this->createNested(); });
 }
 
+CriticalSection CRuntimeStatisticCollection::nestlock;
+
 unsigned __int64 CRuntimeStatisticCollection::getSerialStatisticValue(StatisticKind kind) const
 {
     unsigned __int64 value = getStatisticValue(kind);