[iotg][aaeon] Reboot hangs with 5.13 kernel

[Summary] If you reboot the system by typing in "reboot" on the command line, the system will hang with a blank screen and a frozen cursor. You have to power cycle the system for it to reboot.

If CDTS reboots the system during the reboot stress test, the system will either hang, or boot up into the UEFI shell. If it boots into the UEFI shell, you must enter the BIOS setup, then quit without saving. Only then will it successfully boot from the SSD.

[Steps to reproduce]
Method 1:
Boot the system.
Open a terminal.
Type reboot

Method 2:
Boot the system.
Run CDTS, select Desktop Automated tests.
Select the reboot stress test.

[Expected result]
System should properly reboot.

[Actual result]
Method 1: System hangs. (100%)
Method 2: System hangs. (90%)
          System boots into UEFI shell (10%)

[Failure rate]
Method 1: 100%
Method 2: hangs 90%, reboot into UEFI shell 10%.

[Additional information]
CID: (in process of applying)
SKU:
system-manufacturer: AAEON
system-product-name: UPX-TGL01
bios-version: 5.19
CPU: Intel(R) Celeron(R) 6305E @ 1.80GHz (2x)
GPU: 00:02.0 VGA compatible controller [0300]: Intel Corporation Device [8086:9a78] (rev 01)
kernel-version: 5.13.0-1004-intel

[Stage]
Issue reported and logs collected right after it happened