lmb: reserve common areas during board init

lmb: reserve common areas during board init

The LMB module provides API's for allocating and reserving chunks of
memory which is then typically used for things like loading images for
booting. Reserve the portion of memory that is occupied by the U-Boot
image itself, and other parts of memory that might have been marked as
reserved in the board's DTB. When executing in SPL, reserve the
sections that get relocated to the ram memory, the stack and
the global data structure and also the bss.

Mark these regions of memory with the LMB_NOOVERWRITE flag to indicate
that these regions cannot be re-requested or overwritten.

Signed-off-by: Sughosh Ganu <sughosh.ganu@linaro.org>
Reviewed-by: Simon Glass <sjg@chromium.org>