Debug VFS modules again

[Jagan]

I was able to gdb after the module had been loaded by attaching to the pid
of the forked child smbd for the current connection.

 Gdb accepted a breakpoint in ABC_open (a VFS module loaded function) but
would not break even after I issued an open. It mentioned starting a New
Thread. Does the smbd start a new thread on every request. How can I
gdb/single step through the VFS functions.

On every request.