MRW: Use a distro override to enable providers

Now that obmc-mrw is no longer a machine feature we can organize
a bit and enable MRW providers off to the side with a disto override,
de-cluttering wherever non-MRW defaults are specified.

No functional impact but slightly easier for humans to parse.

Change-Id: If2731206b94e16e0b0132a385756eb11178118f2
Tested: Built a Witherspoon image and validated manifest
Signed-off-by: Brad Bishop <bradleyb@fuzziesquirrel.com>
1 file changed