Documentation/s390: Update / remove developerWorks web links

s390 documentation now lives in IBM Knowledge Center, so update the link
in the zfcpdump documentation.

Also, remove the old developerWorks links from the appldata source code.
Those were not really documentation related, but rather a reminder to the
developer that some documentation has to be adjusted when changing the
record layout, which should still be pretty obvious from the remaining
comment.

Signed-off-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>