Security update for the Linux Kernel (Live Patch 1 for SLE 15 SP5)

This update for the Linux Kernel 5.14.21-150500_55_7 fixes several issues. The following security issues were fixed: - CVE-2023-4921: Fixed a use-after-free vulnerability in the QFQ network scheduler which could be exploited to achieve local privilege escalation (bsc#1215300). - CVE-2023-39198: Fixed a race condition leading to a use-after-free in qxl_mode_dumb_create() (bsc#1217116). - CVE-2023-51780: Fixed a use-after-free in do_vcc_ioctl in net/atm/ioctl.c, because of a vcc_recvmsg race condition (bsc#1218733).