DJGPP: Avoid leaking memory on lowmem mapping error

Add a clarifying comment about why low memory is never unmapped.

Corresponding to flashrom svn r1195.

Signed-off-by: Carl-Daniel Hailfinger <c-d.hailfinger.devel.2006@gmx.net>
Acked-by: Rudolf Marek <r.marek@assembler.cz>
1 file changed