chain.c32: update reactos= option for modern value

chain.c32: update reactos= option for modern value

Changed from "seg=0:0x8000:0x8100" to "seg=0x0F80"

Reactos is "alpha", so the only version of Reactos that its devs support
is the "latest" at each time. Older versions of Reactos are not
relevant / supported by Reactos' devs.

Submitted-By: Ady <ady-sf@hotmail.com>
Old 2011-06-14
https://git.reactos.org/?p=reactos.git;a=blob;f=reactos/boot/freeldr/freeldr/include/arch/pc/x86common.h;hb=28e58e6d01892c1f2f0e1d323745e6463cb9e6c9
https://svn.reactos.org/svn/reactos/trunk/reactos/boot/freeldr/freeldr/include/arch/pc/x86common.h?revision=52226&view=markup

New 2011-06-18
https://git.reactos.org/?p=reactos.git;a=blob;f=reactos/boot/freeldr/freeldr/include/arch/pc/x86common.h;hb=0eb6daaf66127de803d36d45a4eea29d30a7ca36
https://svn.reactos.org/svn/reactos/trunk/reactos/boot/freeldr/freeldr/include/arch/pc/x86common.h?revision=52346&view=markup

Signed-off-by: Gene Cumm <gene.cumm@gmail.com>