sndmasssubl and sig1 / sig2 restarts

[dabail10]

These are purely diagnostic variables, but the CESM test suite checks exact restart with the history files and these are different across a restart. This does not impact the core state variables and would never be noticed when these are off. the sig1 / sig2 variables are only impacted when the C grid is turned on (grid_ice = 'C'). I am working on diagnosing why this is an issue. This was found on derecho intel in debug mode.