Add/Enable option to free memory in mpp_global_field interfaces

[rem1776]

Is your feature request related to a problem? Please describe. mpp_global_field has a routine to free memory, mpp_global_field_free_comm, but it is private and unused. A similar routine is provided for mpp_redistribute and is used via an optional argument so I'm unsure if this was excluded purposefully or just never added to it's intended routine.

Describe the solution you'd like Add a optional argument to the routines in the mpp_global_field interfaces to free the memory if true.

Describe alternatives you've considered Remove the unused routine if freeing the memory isn't worth it.

Additional context https://github.com/NOAA-GFDL/FMS/blob/ab1b0a4cb2beac72d889d94a628e0d02092723b2/mpp/include/mpp_domains_comm.inc#L450-L465