Populate ccpp_scheme_utils::ccpp_constituent_index stub in CAM

[jimmielin]

Issue Type

Infrastructure Update

Issue Description

Currently, the https://github.com/ESCOMP/CAM/blob/cam_development/src/utils/cam_ccpp/ccpp_scheme_utils.F90 stub in CAM only serves to allow code to compile, but it does not interact with the other stub in CAM to get constituent index by standard name. It should be actually written and populated so atmospheric_physics physics schemes can move to use the official framework ccpp_scheme_utils instead of the to_be_ccppized version.

Will this change answers?

No

Will you be implementing this yourself?

Any CAM SE can do this

[jimmielin]

implemented in #1536