Set logical before printing thermodynamically active species in air_composition

### What happened?

Right now, we're printing out `Thermodynamic active species` information for every constituent, regardless of whether it's actually thermodynamically active

`src/data/air_composition.F90`: line ~434

### What are the steps to reproduce the bug?

Add a new constituent via the metadata (`advected = true`) that is not in the case select for thermodynamically active species in air_composition.F90.

Then see that that constituent is listed in the atm.log under "Thermodynamic active species "

### What CAM-SIMA hash were you using?

c99c034a

### What machine were you running CAM-SIMA on?

CGD machine (e.g. izumi)

### What compiler were you using?

GNU

### Path to a case directory, if applicable

_No response_

### Will you be addressing this bug yourself?

Any Software Engineer can do this

### Extra info

What we need is a logical that defaults to .false. and is set to true only if one of the case selects is entered. And then the writing to iulog should only happen for iterations when the logical is .true.