[Bug gcov-profile/94570] -fprofile-dir is broken on Cygwin

[10walls at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94570

--- Comment #7 from jon_y <10walls at gmail dot com> ---
Created attachment 48281
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=48281&action=edit
Alternate patch

I'm not sure if ltmain.sh is shared in the cygnus tree, but this patch should
work too.