illumos issue: https://www.illumos.org/issues/8681
The BIOS memory above 1MB is assumed to be contiguous and we can just
load kernel and modules. Unfortunately it is not true (any more), at least
AMD Ryzen is known to have hole at about 30MB(ish) line.
This patch is not yet fully complete and perfect, I have done basic build/boot,
but I do not have Ryzen to test with; also most likely the metadata needs
Note: the UEFI will need similar solution, but it is a more complicated
there, so we introduce the concept with BIOS.