improve comment about gpgv
improve comment about gpgv

JacksonIsaac/libsolv,jsilhan/libsolv,JacksonIsaac/libsolv,jsilhan/libsolv,jsilhan/libsolv,JacksonIsaac/libsolv,jsilhan/libsolv,JacksonIsaac/libsolv,JacksonIsaac/libsolv,jsilhan/libsolv,jsilhan/libsolv