Remove documentation of configure options, one of which was obsolete.
Remove documentation of configure options, one of which was obsolete.

luaposix/luaposix,jimmyharris/luaposix,jimmyharris/luaposix,rrthomas/luaposix,snegovick/luaposix,rrthomas/luaposix,zevv/luaposix,ardje/luaposix,ardje/luaposix,zevv/luaposix,snegovick/luaposix