Adding FATES subdirectories to PF unit build fails

[ekluzek]

We will want to bring in FATES subdirectories to the main PF unittesting so that we can test both things outside of and inside FATES. And it could be good to run all of the CTSM and FATES tests all together.

But adding FATES subdirectories to the PF unit-test build fails with errors in the FATES endrun calls.

Adding FATES subdirectories to the PF unit build gets a bunch of errors on endrun calls in FATES code like the following:

/glade/work/erik/ctsm_worktrees/newbranch/src/fates/radiation/TwoStreamMLPEMod.F90(1748): error #6498: The use-name for this local-name is not defined.   [ERRMSG]
       call endrun(msg=errMsg(sourcefile, 1748))

It works, if the build is run twice, but if you delete the unit test build directory, and run from scratch it doesn't work. So I'll remove this part.

Originally posted by @ekluzek in #3699 (comment)

[ekluzek]

The draft PR #3251 sidesteps this by having separate tests for the FATES tests.

But, the thing is that there may be cases where we need FATES code in a test of CTSM infrastructure. For example, I saw that I needed some FATES code in order to do a decompInitMod tests.