Trying to add sparse matrix code to LK2/REDUCE_KFF_TO_KAA.f90

[ceanwang]

Yes, just want to try a easy build case.

There could setup a sparse solver switch, like:

If SparseSolver = 'SuperLU' then
  ...
else If SparseSolver = 'PaStiX' then
  ...
else
   print 'Not supported yet'
endif