[LinuxBIOS] memory table address

[Robert Millan]

Hi!

Rudolf reported that GRUB doesn't start on LBv2 because it attempts to find
the memory map table at 0x500, and it isn't always there.  For him it is at
0x530, but looking at the code it seems not to be hardcoded, but instead
right after a GDT that does live at 0x500.  See:

http://grub.enbug.org/LinuxBIOS

Is there a spec on something on what should payloads do about this?  Probe
0x500 and 0x530 or ... ?

TIA