/usr/share/man/man1/mpic++.mpich2.1.gz is in libmpich2-dev 1.4.1-1ubuntu1.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/share/man/man1/mpicxx.mpich2.1.gz
/usr/share/man/man1/mpicxx.mpich2.1.gz