PGI issue: MOM6_SIS2 test crashes under nvhpc22.7 compiler on c5 after mosaic2 update

[nikizadehgfdl]

MOM6_SIS2 tests under pgi compiler nvhpc22.7 crashes with

FATAL from PE    24: character buffer is too small; increase length: netcdf_read_data_0d: file:INPUT/grid_spec.nc- variable:lnd_mosaic

This test runs fine when land_null is reverted back to pre-mosaic2 tag 2020.01-alpha1