Upgrade to Linux 6.1.12-1 from sid (stable branch)

Blocked by:

• Upgrade to Linux 6.1.12-1 from sid (devel branch) (!1055 - merged) (of which this MR is a backport)
• Enable non-free-firmware archive area for distr... (!1036 - merged) (on which this MR is based)
• Test on bare metal
• Analyze test suite results

It fixes several security issues that were fixed via DSA 5324-1 in Bullseye, such as:

• https://security-tracker.debian.org/tracker/CVE-2023-0179
• https://security-tracker.debian.org/tracker/CVE-2023-0266

Closes #19444 (closed)

Most of these changes will be reverted in Tails 6.0: #19467 (closed)