This patch adds support for lazy install of Marvell prestera SDK
drivers for platform-nokia. Lazy install for drivers is added as
updated sdk driver needs to classify the drivers required for platform
during compile time. SDK drivers and platform files are now fetched
from a submodule(mrvl-prestera).
Additionaly, DTB required for sonic_fit creation during compile time
is sourced from sonic-linux-kernel.
Change-Id: Id5b011e6bd67accf7b1579d91cb7affad464e916
Signed-off-by: Pavan Naregundi <pnaregundi@marvell.com>
