It makes Bochs > 2.2.6 fail with "[MEM0 ] ROM: System BIOS must end at 0xfffff"
and, according to http://www.nabble.com/Strange-error-message-when-bringing-up-a-CVS-build-td7532679.html
isn't even necessary for 2.2.6
# Write bochsrc.txt configuration file.
open (BOCHSRC, ">", "bochsrc.txt") or die "bochsrc.txt: create: $!\n";
print BOCHSRC <<EOF;
-romimage: file=\$BXSHARE/BIOS-bochs-latest, address=0xf0000
+romimage: file=\$BXSHARE/BIOS-bochs-latest
vgaromimage: file=\$BXSHARE/VGABIOS-lgpl-latest
boot: disk
cpu: ips=1000000