sbpcd.c: removes bogus duplicate definition of sbpcd_lock, use of
CURRENT (we are using private queue) and call of invalidate_buffers() in
->media_changed() (caller does it itself).  That went in a changeset from
davej - looks like a merge problem...
	sr.c: braino in ifdefed printk - s/disk/cd->disk/.  Thanks to jejb
for spotting that one...