__bdevname now only prints major/minor number which isn't much help.  So
remove most calls to it from md.c, replacing those that are useful by calls
to bdevname (often printing the message when the error is first detected
rather than higher up the call tree).

Also discard hot_generate_error which doesn't do anything useful and never
has.
Signed-off-by: Neil Brown <neilb@cse.unsw.edu.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>