switching-sched.txt: remove 'as' for as is no longer supported

The patch is against 3.1-rc3.

as is no longer supported and we can not use 'elevator=as' any more.

Signed-off-by Wang Sheng-Hui <[email protected]>

---
 Documentation/block/switching-sched.txt |    4 ++--
 1 files changed, 2 insertions(+), 2 deletions(-)

Documentation/block/switching-sched.txt +2 -2

index 71cfbdc..3b2612e 100644
@@ -1,6 +1,6 @@
 To choose IO schedulers at boot time, use the argument 'elevator=deadline'.
-'noop', 'as' and 'cfq' (the default) are also available. IO schedulers are
-assigned globally at boot time only presently.
+'noop' and 'cfq' (the default) are also available. IO schedulers are assigned
+globally at boot time only presently.
 
 Each io queue has a set of io scheduler tunables associated with it. These
 tunables control how the io scheduler works. You can find these entries