/usr/lib/gcc-cross/mips64el-linux-gnuabi64/5/liblto_plugin.so is in cpp-5-mips64el-linux-gnuabi64 5.5.0-12ubuntu1cross1.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/gcc-cross/mips64el-linux-gnuabi64/5/liblto_plugin.so.0.0.0