seeds: rename seeds with multiplatform enabled

all those seeds actually allow other platforms,
even if non-OMAP, to build together. We'll rename
them and provide versions of these seeds without
multiplatform selected.

Signed-off-by: Felipe Balbi <balbi@ti.com>
seeds: add non-multiplatform seeds

all those seeds are the same as the multiplatform
versions, but without multiplatform.

Signed-off-by: Felipe Balbi <balbi@ti.com>