Merge branch 'mark-petersen/ocean/fix_layerthickness_call' into next …

…(PR #3239)

Fix ocean layerThickness call

This PR brings in a new mpas-source submodule that fixes an issue with
mpas-ocean uncovered by debug tests with intel-19. A layerThickness
pointer was passed into a subroutine but it is unassociated, and never
used in that subroutine. This change simply removes the unused variable
from both the calling and called routines.

Fixes #3190
[BFB]