Support fw_cfg data source

This bug was originally filed in Launchpad as [LP: #1879294](https://bugs.launchpad.net/cloud-init/+bug/1879294)

Launchpad details

affected_projects = []

assignee = None

assignee_name = None

date_closed = None

date_created = 2020-05-18T09:46:08.422975+00:00

date_fix_committed = None

date_fix_released = None

id = 1879294

importance = wishlist

is_complete = False

lp_url = https://bugs.launchpad.net/cloud-init/+bug/1879294

milestone = None

owner = soren

owner_name = Soren Hansen

private = False

status = triaged

submitter = soren

submitter_name = Soren Hansen

tags = []

duplicates = []

_Launchpad user **Soren Hansen(soren)** wrote on 2020-05-18T09:46:08.422975+00:00_

It would be awesome if cloud-init supported pulling config from QEMU's fw_cfg. There has been kernel support for it since around 4.15 (IIRC), so it should be widely available at this point.

Related bugs:
* bug 1879294: Support fw_cfg data source
* bug 1753558: NoCloud should use "OEM Strings" instead of
system-serial-number