ARCH: SPL: Add parametric board initializer

ARCH: SPL: Add parametric board initializer

Add a structure for table-driven configuration mechanism such that no recompilation
is needed to update the configuration parameters, rather than hard-coding
board initialization parameters.

Signed-off-by: Che-Liang Chiou <clchiou@chromium.org>
Signed-off-by: Abhilash Kesavan <a.kesavan@samsung.com>
Signed-off-by: Tom Wai-Hong Tam <waihong@chromium.org>
Signed-off-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Rajeshwari Shinde <rajeshwari.s@samsung.com>
Signed-off-by: Minkyu Kang <mk7.kang@samsung.com>