Staging: autofs3: fix up TODO

As per Peter's request, move people to autofs4, don't fix up autofs3.

Cc: Arnd Bergmann <arnd@arndb.de>
Cc: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/staging/autofs/TODO

-- step up and maintain this filesystem to ensure that it continues to
-  work.  There are lots of reported autofs3 bugs, and it uses the BKL,
-  which is going away.
-  If this does not happen, the will be removed in the 2.6.38 kernel
-  release.
+- Work to help people to migrate to autofs4.
+- This filesystem will be removed in the 2.6.38 kernel release.
 
 Please send patches to Greg Kroah-Hartman <greg@kroah.com> and
 Cc: H. Peter Anvin <hpa@zytor.com> and Arnd Bergmann <arnd@arndb.de>