Platform identifies the image runtime requirements
Platform identifies the image runtime requirements

It should be clarified that the manifest is describing what is
'in the image', not what 'it will run on'.

Signed-off-by: Matt Spencer <0ba2c28040c9bdb07663c27f3795e28b2d583b58@arm.com>

jonboulle/image-spec,opencontainers/image-spec,opencontainers/image-spec,vbatts/oci-image-spec,mattspencer-arm/image-spec,jonboulle/image-spec,vbatts/oci-image-spec,mattspencer-arm/image-spec