Add top-level attributes for git M-P packages

var/spack/repos/builtin/packages/macsio/package.py

var/spack/repos/builtin/packages/mad-numdiff/package.py

var/spack/repos/builtin/packages/mallocmc/package.py

var/spack/repos/builtin/packages/masa/package.py

var/spack/repos/builtin/packages/mdtest/package.py

var/spack/repos/builtin/packages/mefit/package.py

var/spack/repos/builtin/packages/meraculous/package.py

var/spack/repos/builtin/packages/mfem/package.py

var/spack/repos/builtin/packages/mindthegap/package.py

var/spack/repos/builtin/packages/miniaero/package.py

var/spack/repos/builtin/packages/miniasm/package.py

var/spack/repos/builtin/packages/mitos/package.py

var/spack/repos/builtin/packages/mlhka/package.py

var/spack/repos/builtin/packages/mofem-cephas/package.py

...k/repos/builtin/packages/mofem-fracture-module/package.py

...uiltin/packages/mofem-minimal-surface-equation/package.py

var/spack/repos/builtin/packages/mpich/package.py

var/spack/repos/builtin/packages/mpifileutils/package.py

var/spack/repos/builtin/packages/mpilander/package.py

var/spack/repos/builtin/packages/mpir/package.py