Add capability to send both prescribed SST and multi-level ocean SST/SALN to mediator

[mvertens]

Description of changes

Add capability to send both prescribed SST and multi-level ocean SST/SALN to mediator

Specific notes

This PR addresses the use case where an F compset is configured with prognostic CISM.
CAM requires prescribed SST values while CISM requires both input from CLM as well as multi-level ocean input from the ocean component.

Contributors other than yourself, if any: None

CDEPS Issues Fixed: None

Are there dependencies on other component PRs (if so list): No

Are changes expected to change answers: bfb

Any User Interface Changes (namelist or namelist defaults changes): Yes

• new compset configuration DOCN%MULTILEV-DOM has been added
• new namelist setting datamode = "multilev_dom" will be generated if DOCN%MULTILEV-DOM is in the compset

Testing performed (e.g. aux_cdeps, CESM prealpha, etc):
Verified that the following case gave correct behavior:

./create_newcase --case <casename>  \\
--compset 1850_CAM60_CLM51%SP_CICE_DOCN%MULTILEV-DOM_MOSART_CISM2%AIS-EVOLVE%GRIS-EVOLVE_SWAV_SESP \\
--res a%0.9x1.25_l%0.9x1.25_oi%tnx1v4_r%null_g%ais8:gris4_w%null_z%null_m%tnx1v4 \\
--run-unsupported

Hashes used for testing: