V4L/DVB (3336): Bt8xx documentation authors fix

- use one Author per line, which allows us to add more
authors later without creating a mess.
- Add Michael Krufky due to -git commit
2cbeddc976645262dbe036d6ec0825f96af70da3

Signed-off-by: Michael Krufky <[e-mail]>
Signed-off-by: Mauro Carvalho Chehab <[e-mail]>

Documentation/dvb/bt8xx.txt

···
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 --
-Authors: Richard Walker, Jamie Honan, Michael Hunold, Manu Abraham
+Authors: Richard Walker,
+	 Jamie Honan,
+	 Michael Hunold,
+	 Manu Abraham,
+	 Michael Krufky