lib: Fix warning when debug logs are disabled
lib: Fix warning when debug logs are disabled

Fix warning in sync.c when debug logs are not enabled

https://bugs.freedesktop.org/show_bug.cgi?id=56439

rmarku/libfprint,Gnate/libfprint,ccsystems/libfprint,abhishekgahlot/fprint-bsapi,anarsoul/libfprint,FabriceSalvaire/libfprint-baspi,micw/libfprint,hyperair/fprint-bsapi,PDXostc/libfprint,abhishekgahlot/fprint-bsapi,zOrg1331/libfprint,FabriceSalvaire/libfprint-baspi,jipumarino/libfprint,freedesktop-unofficial-mirror/libfprint__libfprint,yingted/etes603,ccsystems/libfprint,rmarku/libfprint,FabriceSalvaire/libfprint-baspi,jipumarino/libfprint,payden/libfprint,PDXostc/libfprint,jipumarino/libfprint,hyperair/fprint-bsapi,abhishekgahlot/libfprint,yingted/etes603,micw/libfprint,zOrg1331/libfprint,anarsoul/libfprint,hyperair/fprint-bsapi,payden/libfprint,zOrg1331/libfprint,abhishekgahlot/libfprint,sbambrough/libfprint_extended,Gnate/libfprint,rmarku/libfprint,yingted/etes603,abhishekgahlot/libfprint,freedesktop-unofficial-mirror/libfprint__libfprint,micw/libfprint,zemen/libfprint,zemen/libfprint,Gnate/libfprint,iafilatov/libfprint,abhishekgahlot/fprint-bsapi,freedesktop-unofficial-mirror/libfprint__libfprint,payden/libfprint,zemen/libfprint,sbambrough/libfprint_extended,PDXostc/libfprint,sbambrough/libfprint_extended,ccsystems/libfprint