[S390] move crypto options and some cleanup.

This patch moves the config options for the s390 crypto instructions
to the standard "Hardware crypto devices" menu. In addition some
cleanup has been done: use a flag for supported keylengths, add a
warning about machien limitation, return ENOTSUPP in case the
hardware has no support, remove superfluous printks and update
email addresses.

Signed-off-by: Jan Glauber <jan.glauber@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>