s390: fix zfcpdump-config

zipl from s390-tools generates root=/dev/ram0 kernel cmdline for
zfcpdump, thus BLK_DEV_RAM is required.

zfcpdump initrd mounts DEBUG_FS, thus is also required.

Bug-Ubuntu: https://launchpad.net/bugs/1722735
Bug-Ubuntu: https://launchpad.net/bugs/1719290



Signed-off-by: Dimitri John Ledkov <xnox@ubuntu.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>