opensc-explorer: avoid warnings on readline-less builds
opensc-explorer: avoid warnings on readline-less builds

philipWendland/OpenSC,AktivCo/OpenSC,rickyepoderi/OpenSC,hhonkanen/OpenSC,mouse07410/OpenSC,Jakuje/OpenSC,dengert/OpenSC,Jakuje/OpenSC,fabled/OpenSC,fabled/OpenSC,viktorTarasov/OpenSC-SM,hongquan/OpenSC-main,fabled/OpenSC,OpenSC/OpenSC,OpenSC/OpenSC,fabled/OpenSC,metsma/OpenSC,metsma/OpenSC,mouse07410/OpenSC,CardContact/OpenSC,rickyepoderi/OpenSC,metsma/OpenSC,LudovicRousseau/OpenSC,hongquan/OpenSC-main,hhonkanen/OpenSC,frankmorgner/OpenSC,philipWendland/OpenSC,AktivCo/OpenSC,Jakuje/OpenSC,Jakuje/OpenSC,dengert/OpenSC,hhonkanen/OpenSC,frankmorgner/OpenSC,viktorTarasov/OpenSC-SM,OpenSC/OpenSC,frankmorgner/OpenSC,frankmorgner/OpenSC,CardContact/OpenSC,hongquan/OpenSC-main,LudovicRousseau/OpenSC,viktorTarasov/OpenSC-SM,philipWendland/OpenSC,rickyepoderi/OpenSC,dengert/OpenSC,LudovicRousseau/OpenSC,CardContact/OpenSC,mouse07410/OpenSC,AktivCo/OpenSC