s390/dasd: fix Oops in dasdaliasgetstartdev due to missing pavgroup
This is an automated ID intended to aid in discovery of potential security vulnerabilities. The actual impact and attack plausibility have not yet been proven. This ID is fixed in Linux Kernel version v4.19.260 by commit aaba5ff2742043705bc4c02fd0b2b246e2e16da1, it was introduced in version v2.6.25 by commit 8e09f21574ea3028d5629e5de759e0b196c690c5. For more details please see the references link.