[Midnightbsd-cvs] src: btx.S: Use real mode to invoke BIOS routines rather than virtual 86

[laffer1 at midnightbsd.org]

Log Message:
-----------
Use real mode to invoke BIOS routines rather than virtual 86 mode.

Obtained from: FreeBSD 7.1 circa Aug 2008

Modified Files:
--------------
    src/sys/boot/i386/btx/btx:
        btx.S (r1.3 -> r1.4)
        (http://cvsweb.midnightbsd.org/src/sys/boot/i386/btx/btx/btx.S?r1=1.3&r2=1.4)