Add a replicated field to the data structure instead of checking the replication on the value of loc2glob

• Fortran users may want the loc2glob array to be allocated for them in case or check of the spm data structure that may reallocate the arrays. In that case, it is difficult to know if we need to allocate the array or not in spmInit. Thus, this PR adds a replicated field in the data structure that indicates if the matrix is replicated on all involved nodes (value of 1), or if it is distributed among them (value of 0).

• the spmAlloc function is updated to do the associated allocation.