CVE-2022-50564 s390/netiucv: Fix return type of netiucv_tx()

In the Linux kernel, the following vulnerability has been resolved: s390/netiucv: Fix return type of netiucvtx With clang's kernel control flow integrity kCFI, CONFIGCFICLANG, indirect call targets are validated against the expected function pointer prototype to make sure the call target is valid...