add delay around sl82c105_reset_engine calls

The hald media changed polling does really confuse things.
Noone knows why the delays are needed, but they give us access to the CD.

An udelay(50) will give reliable access to the drive, but there is still
one (or more) EH reset. The drive works without EH resets with udelay(100).

Signed-off-by: Olaf Hering <olaf@aepfle.de>
Signed-off-by: Jeff Garzik <jeff@garzik.org>