s390/ipl: avoid adding scpdata to cmdline during ftp/dvd boot

Add missing ipl parmblock validity check to append_ipl_scpdata.

Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
1 file changed