Description of problem:

Say that I am booting "rescue" and with filesystems mounted
"read-only".  Now I would like to have _some_ of these writable
too.  If I will try 

   mount -o rw,remount /mnt/sysimage/some/file/system

then I am greeted with

   warning: can't open /etc/fstab: No such file or directory

and the same if I will attempt a remount by a device name.

Yes, I know how to deal with the situation but 

   cd /etc && ln -s mtab fstab

helps as well.  It would be nice if anaconda could just provide
that link, if only in a "rescue" mode.  Really handy especially
if I have to explain somebody what to do while talking over a phone. :-)