[PATCH] CPUSETS: add mems to basic usage documentation

[Simon Horman <horms@verge.net.au>]

It seems that there must be at least one node in mems
and at least one CPU in cpus in order to be able to assign
tasks to a cpuset. This makes sense. And I think it would
also make sense to include a mems setting in the basic usage
section of the documentation.

I also wonder if something logged to dmsg, explaining why
a write failed, would be a good enhancement. I ended up having
rummage arround in cpuset.c in order to work out why my 
configuration was failing.

Signed-off-by: Simon Horman <horms@verge.net.au>

Index: linux-2.6/Documentation/cpusets.txt
===================================================================
--- linux-2.6.orig/Documentation/cpusets.txt	2007-03-30 13:03:07.000000000 +0900
+++ linux-2.6/Documentation/cpusets.txt	2007-03-30 13:03:19.000000000 +0900
@@ -557,6 +557,9 @@
 Add some cpus:
 # /bin/echo 0-7 > cpus
 
+Add some mems:
+# /bin/echo 0-7 > mems
+
 Now attach your shell to this cpuset:
 # /bin/echo $$ > tasks