control: Expose fanctl dump option in YAML mode

While the fan control code that uses the YAML configuration doesn't have
any dump capabilities, there are testcases in the
openbmc-test-automation repo that call fanctl dump that don't know if
it's available or not.

This commit just exposes the 'dump' option even in YAML mode so that the
testcase doesn't need to care about fan control's internal
configuration.  There was already code that would write the following to
/tmp/fan_control_dump.json in YAML mode:

"msg": "Unable to create dump on non-JSON config based system"

I also changed the help text to a more generic statement about dumping
data debug as opposed to saying it just dumps the flight recorder, since
it does a lot more.

Signed-off-by: Matt Spinler <spinler@us.ibm.com>
Change-Id: I119b733628402d0719fd42b90254d7072245d080
1 file changed