Merged
requested to merge basmundhopk/mlib_devel:brett/handle-empty-user-ip-ports into rfsocs/vmc-refactor
gen_block_file.m can generate a module with an empty ports: entry when the module has no external ports (gateway-in & gateway-out). When parsed from YAML, this value becomes None. Probably won't happen in any real applications, but came up during testing.
_instantiate_user_ip() currently assumes usermodule['ports'] is always iterable, causing the backend to fail with:
TypeError: 'NoneType' object is not iterable