Add RRTMGP initialization flags and revert hardcoding of mpiroot#17

BinLiu-NOAA merged 1 commit into

hafs-community:feature/hafsv2_synchafs-community/ufsatm:feature/hafsv2_syncfrom

dustinswales:feature/add_rrtmgp_init_flagdustinswales/fv3atm:feature/add_rrtmgp_init_flagCopy head branch name to clipboard