meta-google: ipmi-config: Add option to remove default entity config

Currently it fources all gBMC to have `[]` as the entity-mapping config
and will cause an issue to gBMC systems that uses the default mapping.
Add a way to remove the default isntead of having all gBMC automatically
remove it.

ENTITY_MAPPING="default"
```
$ cat ./tmp/work/all-openbmc-linux/phosphor-ipmi-config/1.0-r1/package/usr/share/ipmi-providers/entity-map.json
[
    {
        "id": 0,
        "containerEntityId": 30,
        "containerEntityInstance": 0,
        "isList": false,
        "isLinked": false,
        "entities": [
            {
                "id": 11,
                "instance": 3
            },
            {
                "id": 11,
...
```

ENTITY_MAPPING="no"
```
$ cat ./tmp/work/all-openbmc-linux/phosphor-ipmi-config/1.0-r1/package/usr/share/ipmi-providers/entity-map.json
[]

```

Change-Id: I9adccc2685055bad8ac27207305083ba40327ce2
Signed-off-by: Willy Tu <wltu@google.com>

0 files changed, 0 insertions, 0 deletions