The current defconfigs are BIOS-specific which makes it difficult to maintain
multiple defconfigs for boards running the same BIOS.
This patch re-organizes the defconfigs to be board-specific. A command line
option BOARD is introduced to specify a board on which the current build targets
at. The original PLATFORM is kept for backward compatibility which redirects to
apl-mrb and nuc6cayh for sbl and uefi, respectively.
The getting started guide is also updated accordingly.
v1 -> v2:
* Rewrite 'up2' to 'UP2'.
Tracked-On: #1588
Signed-off-by: Junjie Mao <junjie.mao@intel.com>
Reviewed-by: Anthony Xu <anthony.xu@intel.com>
Junjie Mao