Fix string length with ifort.

It doesn't like actual arguments that are shorter than the dummy
argument.
Fix typo in mesher dependencies.
Remove constants module from solver list.

Make clean in the specfem3d directory would incorrectly remove the
module, but not the object. Consequently, it would not be rebuilt.
Add arguments to ADIOS stubs.

This causes unused variable warnings, but because of ifort's
-gen-interfaces, the number of arguments needs to be the same for both
the real functions and the stubs.