[PWGLF] Use std::abs for charge comparison (#17489)

Author: njacazio

PWGLF/Utils/inelGt.h

@@ -114,7 +114,7 @@ struct ParticleCounter {
         continue;
       }
       // is charged
-      if (abs(p->Charge()) == 0) {
+      if (std::abs(p->Charge()) == 0) {
         continue;
       }
       // in acceptance