All Coffee Lake mainboards use the default value for the setting
`SataMode`. Thus, drop it from their devicetree.
Change-Id: Ibb329eb8b752c2220bb25f14fb6ae92dd8a308d6
Signed-off-by: Felix Singer <felixsinger@posteo.net>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/59889
Reviewed-by: Angel Pons <th3fanbus@gmail.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>