(rlogin): If `buffer' arg is a buffer object, initialize buffer-name to the

(rlogin): If `buffer' arg is a buffer object, initialize buffer-name to the
buffer name.
Set `buffer' to buffer actually created or returned by get-buffer-create.
Set `proc' to the process actually in the new buffer, not the process
with the name buffer-name; they may not be the same if buffers have bee
renamed.