/usr/bin/mips64el-linux-gnuabi64-gnatxref is in gnat-8-mips64el-linux-gnuabi64 8-20180414-1ubuntu2cross1.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/bin/mips64el-linux-gnuabi64-gnatxref-8
/usr/bin/mips64el-linux-gnuabi64-gnatxref-8