Add restart flag inconsistency check

[njeffery]

It's possible to run mpas-seaice with inconsistent restart flags.

Snow and BGC tracers have independent namelist restart flag options. Although E3SM turns these flags to true during restarts, there is no requirement in stand alone mpas runs. The purpose of tracer specific restarts is to allow continuation of a spun-up run that may not have had these tracers active to be used as an initial condition for runs with the tracers active. However, for most stand alone runs, inconsistent restart flags would lead to non-bfb restartability errors.

Fix: add an error check and message during initialization to stop the run if restart flags are inconsistent.