Bring TT bootloader features to T1 bootloader

[tsusanka]

Idea from Asana backlog. It will probably be too much engineering but I am still curious what it takes and whether it is even possible.

[tsusanka]

Unless we decide to change the memory layout on T1 (so we can have bigger bootloader on T1) we can't do this.

[prusnak]

Checklist:

• [ ] Ed25519 COSI signatures
• [x] parse VERSION and FIX_VERSION from the firmware header (7d93bd3)
• [ ] warn when firmware downgrade is happening
• [ ] warn when firmware downgrade with erase (new VERSION < old FIX_VERSION) is happening
• [x] erase the storage when new VERSION < old FIX_VERSION (7d93bd3)

[andrewkozlik]

• [ ] Add MAX_BOOTLOADER_VERSION to firmware header, which will correspond with the maximum bootloader version listed in bl_check.c.
• [ ] Don't allow user to downgrade if BOOTLOADER_VERSION > MAX_BOOTLOADER_VERSION, because it makes the firmware inoperable.

[Hannsek]

I assume we can close this as not planned, right?