Always break nodes for self-modifying code even for backwards writes, because
unconditional jumps are optimized. Fixes an issue with BEFI (
http://board.flatassembler.net/topic.php?p=103896#103896
)


git-svn-id: https://dosemu.svn.sourceforge.net/svnroot/dosemu/trunk@1989 7758b857-130e-0410-ab9c-d8735a528d18