[PATCH] md: fix return code in set_disk_faulty()

[PATCH] md: fix return code in set_disk_faulty()

From: NeilBrown <neilb@cse.unsw.edu.au>

 Following are 10 patches for md in 2.6.1-lastest.

 1-6 are simple bugfixes that I am confident should be in 2.6.2.

 7 is a bugfix that is fairly important, but could probably do with a
 bit more testing first.  It is not impossible that it could deadlock,
 though I think I have caught and fixed all the problems.

 8-10 are code simplication.

 So maybe 7-10 should only go in -mm for now, but if it is a while
 before 2.6.2, then maybe they can go in a 2.6.2-pre.

From: Mike Tran <mhtran@us.ibm.com>

 If cannot find the device, return error (ENODEV) Otherwise, return success
 (0)