Add set bad lba function in md-faulty module.

Hi all:
In order to test md code, sometime we need simulate read/write harddisk error.
Using hdparm --make-bad-sector to simulate read error.But I did not find way of simulating write-error. I tested md-faulty module, it can do this.But it is not provide the function link hdparm --make-bad-sector,which did not set lba. Using hdpamr --make-bad-sector to simulate read error can cause some problem.
It will cause ata commnd reset,disk reset and so on.It take too log time.
So I think add a function in md-faulty which can set read/write lba.
How about ?

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kedacomkernel
2012-05-14

I don't know how --make-bad-sector works so it might not be possible to get md to respond to the same command. But if it can work it sounds like a good idea.

Patches welcome.

NeilBrown