This is a replacement for the original patch given by Ingo.  This one comes
from Monty.
The problem is that merge files now use unix style pathnames on all 
platforms.  The merge file open code was not properly converting those
pathnames back to non-unix when necessary.


myisammrg/myrg_open.c:
  use fn_format to convert pathnames if the files in the merge file have a pathname
mysys/my_getwd.c:
  add a test for '/' in the code that determines if a string inlucdes a pathname