rv-virt support different size of ksram and pgmem region, but the
fixed value in the link script limits this function. As nuttx supports
preprocessing the link script. It is better to use the config value
to compute the memory layout. This also make all kernel build use the
same script.
Signed-off-by: Inochi Amaoto <inochiama@outlook.com>
44bed119f0