ilwork in sumgat is not used

[yangf4]

ilwork is not used in sumgat subroutines:
https://github.com/PHASTA/phasta/blob/master/phSolver/common/mpitools.f#L110
https://github.com/PHASTA/phasta/blob/master/phSolver/common/mpitools.f#L151

And sumgat is called at many places as sumgat(n,u,sum,ilwork). For example, here:
https://github.com/PHASTA/phasta/blob/master/phSolver/compressible/solgmr.f#L126

so we have more actual than formal arguments in sumgat. This is fine but not proper.