`edl` doesn't write the slot bootable and retry count metadata

[adeebshihadeh]

On a freshly provisioned device flashed only with QDL, you get:

-----------------------------
UEFI Total : 926 ms
POST Time      [ 3623] OS Loader
Loader Build Info: Oct 26 2024 02:02:18
comma 845 Agnos bootloader
VB: RWDeviceState: Succeed using devinfo!
Launching fastboot
Fastboot Build Info: Oct 26 2024 02:02:17
qusb2_1: hstx: 4
PLL1 locked: 5
usb_lane: 0
Fastboot: Initializing...
Fastboot: Processing commands
Failed to initialize touch: 3
Could not initialize touch: 3
Maximum boot temp check passed!
Skipping fastboot, use QDL!
Slot _a is unbootable, trying alternate slot
Err: line:1522 FindBootableSlot() status: Load Error
Err: line:1060 LoadImageAndAuth() status: Load Error
UsbfnDwcTransfer: Ep 1, EpDir 1: USB cable not attached, cannot transfer data
UsbDeviceSend: Failed to submit data transfer: Not Ready
Exit key detection timer
Press any key to shutdown

We should copy whatever fastboot does in this case. Probably need to update https://github.com/commaai/flash too.