capgen's Fortran parser does not allow array bounds which are not Fortran identifiers

[climbfuji]

Description

capgen cannot parse array declarations that use an explicit lower bound, for example as in this line with the lower bound being an argument to the scheme:
https://github.com/ufs-community/ccpp-physics/blob/44700d5e92f00524ade276062e1f7c50e554c0fb/physics/SFC_Models/Lake/CLM/clm_lake.f90#L364

Steps to Reproduce

MISSING @dustinswales will create a test for this so that it can be reproduced and fixed easily

Please provide detailed steps for reproducing the issue.

1. step 1
2. step 2
3. see the bug...

Additional Context

This is a valid Fortran expression that capgen needs to be able to process

Output

MISSING

[gold2718]

I am changing the title because I believe the problem is not the lower bound -- that seems to be okay.
The issue is that the parser does not know how to handle any array bound which is not a simple Fortran identifier.
There has been a doctest demonstrating this from the beginning.

Now to work on removing that restriction . . .

[dustinswales]

@climbfuji @gold2718
To work around this in the CCPP SCM, I modified the lower bounds in the scheme from:
-nlevsnow+1 to nlevs1
-nlevsnow+0 to nlevs0

The parsing issue still remains, but not an issue for unification.