Fix compile warning in nl-list-caches
Fix compile warning in nl-list-caches

mshirley/libnl,vyos/libnl3,kolyshkin/libnl,greearb/libnl-ct,congwang/libnl,claudelee/libnl,HolyShitMan/libnl-1,yinquan529/platform-external-libnl,cfriedt/libnl,kolyshkin/libnl,xin3liang/platform_external_libnl,bcopeland/android_libnl,HolyShitMan/libnl-1,yinquan529/platform-external-libnl,Distrotech/libnl,cfriedt/libnl,UnicronNL/libnl3,vyos/libnl3,claudelee/libnl,UnicronNL/libnl3,HolyShitMan/libnl-1,teto/libnl_old,mshirley/libnl,Omegaphora/external_libnl,houstar/libnl,dsahern/libnl,houstar/libnl,dsahern/libnl,UnicronNL/libnl3,geekboxzone/lollipop_external_libnl,teto/libnl_old,congwang/libnl,geekboxzone/lollipop_external_libnl,Distrotech/libnl,gxk/libnl,thiz11/platform_external_libnl,honsys/libnl,tgraf/libnl,Distrotech/libnl,karlhiramoto/libnl,cfriedt/libnl,thiz11/platform_external_libnl,kolyshkin/libnl,chitranshi/libnl,geekboxzone/mmallow_external_libnl,honsys/libnl,baloo/libnl,android-ia/platform_external_libnl,vyos/libnl3,cyclops8456/libnl3,chitranshi/libnl,houstar/libnl,claudelee/libnl,tklauser/libnl,tgraf/libnl,congwang/libnl,UnicronNL/libnl3,houstar/libnl,mshirley/libnl,cyclops8456/libnl3,thom311/libnl,honsys/libnl,thom311/libnl,dsahern/libnl,xin3liang/platform_external_libnl,teto/libnl_old,chitranshi/libnl,tgraf/libnl,dsahern/libnl,gxk/libnl,vyos/libnl3,CyanogenMod/android_external_libnl,geekboxzone/mmallow_external_libnl,baloo/libnl,tklauser/libnl,tklauser/libnl,karlhiramoto/libnl,cyclops8456/libnl3,cfriedt/libnl,claudelee/libnl,karlhiramoto/libnl,gxk/libnl,honsys/libnl,socketpair/libnl,cyclops8456/libnl3,HolyShitMan/libnl-1,chitranshi/libnl,bcopeland/android_libnl,karlhiramoto/libnl,baloo/libnl,greearb/libnl-ct,congwang/libnl,mshirley/libnl,Omegaphora/external_libnl,socketpair/libnl,baloo/libnl,Distrotech/libnl,thom311/libnl,tklauser/libnl,kolyshkin/libnl,socketpair/libnl,teto/libnl_old,android-ia/platform_external_libnl,tgraf/libnl,greearb/libnl-ct,CyanogenMod/android_external_libnl