Regression: Instant reboot on Core Ultra (Meteor Lake) with microcode 20260811 (rev 0x2a)

Updating `intel-ucode` to release `20260811` (which bumps revision from `0x28` to `0x2a` for file `06-aa-04`) causes an immediate hardware reboot during early boot right after selecting the kernel entry in `systemd-boot`.

No `dmesg` or kernel crash logs are saved due to the reboot occurring in the early microcode loading phase.

### System Info
* **Device:** Lenovo ThinkPad T14s Gen 5
* **BIOS Version:** `N46ET26W (1.16)` (Date: 04/29/2026)
* **Embedded Controller (EC):** `N46HT18W`
* **CPU:** Intel Core Ultra 7 155U (Family 6, Model 170 / `0xAA`, Stepping 4)
* **Affected Microcode File:** `intel-ucode/06-aa-04`
* **Kernel / OS:** Arch Linux, kernel `7.1.8-arch1-3`
* **Bootloader:** `systemd-boot`
* **Working Revision:** `0x28` (release 20260512)
* **Failing Revision:** `0x2a` (release 20260811)

### Steps to Reproduce & Workaround
1. Update `intel-ucode` to release `20260811`.
2. Boot system with `initrd /intel-ucode.img` configured in `systemd-boot`.
3. Select kernel entry — system instantly triggers a hardware reboot.
4. **Workaround:** Downgrading `intel-ucode` to release `20260512` (revision `0x28`) restores normal boot behavior.

### Update / Root Cause

Lenovo released BIOS version **`1.17` (`N46UR12W`)** on **11 Aug 2026**. The changelog explicitly mentions:
> `- (New) Updated the CPU Microcode to version 0x2a (CPUID: 0xA06A4)`

#### Findings:
1. **On BIOS 1.16 (`N46UR11W`):** Early loading microcode `0x2a` via `initrd` causes an instant hardware reset during early kernel initialization.
3. **Workaround via `dis_ucode_ldr`:** Adding `dis_ucode_ldr` to the kernel command line allows the system to boot successfully on BIOS 1.16 even with `intel-ucode.img` present in `initrd`, confirming the crash occurs strictly within the OS early microcode loader.
3. **On BIOS 1.17 (`N46UR12W`):** System boots normally without issues because microcode `0x2a` is already baked into the system firmware.

Updating to vendor BIOS 1.17 works as a permanent fix, but applying early microcode updates via OS `initrd` on recent prior BIOS releases (like 1.16) should ideally not result in early-boot hardware crashes.

Start with intel-ucode/06-aa-04 and compare revisions 0x28 and 0x2a from releases 20260512 and 20260811. Reproduce on BIOS 1.16 using systemd-boot, with and without dis_ucode_ldr, then compare against BIOS 1.17. Done requires establishing a safe project-level response to the early-boot reboot.

Written by the indexing model from the issue text.