Update build namelist checks for valid landuse v2 mode combinations

[glemieux]

Description of changes

This ports changes made via https://github.com/glemieux/E3SM/tree/landuse-v2-modechecks to ctsm.

Specific notes

This adds a new switch use_fates_lupft to replace the previous checks on flandusepftdat as well as adding new namelist build checks for valid fates run mode combinations including use_potentialveg.

Contributors other than yourself, if any: @ckoven

Testing performed, if any:
Build and run testing TBD

[glemieux]

The basic fates landuse v2 build namelist options should be all set, but I need to flesh out the graceful failure checks and add unit tests to exercise them.

To do:

• add build namelist failure modes
• add namelist unit tests

[glemieux]

Mode checks:

use_fates_luh

• use_fates_sp must be false
• add fluh_timeseries and check

use_fates_potentialveg

• use_fates_luh must be .true.
• fates_harvest_mode must not be greater than zero

use_fates_lupft

• use_fates_luh must be .true.
• add flandusepftdat and check
• use_fates_nocomp and use_fates_fixedbiogeog must be .true.

fates_harvest_mode

• if greater than two use_fates_luh must be .true.