Reduce "Explicit interface or EXTERNAL declaration is required" compiler warnings in sfcsub#312

rhaesung merged 6 commits intoufs-community:ufs/devufs-community/ccpp-physics:ufs/devfrom

NickSzapiro-NOAA:warning_explicit_sfcsubNickSzapiro-NOAA/ccpp-physics:warning_explicit_sfcsubCopy head branch name to clipboard