Initialization of u16 arrays broken

If we do something like
```
static list_known_crc: u16[5]  = [ 0xd4b0, 0x3340, 0x6a79, 0xe714, 0xe3c1 ];
```
with the IR compiler we actually compute the whole thing as a 32-bit array and then try to copy it over. In addition to having the wrong values, this can overwrite other things.

I think it is a type inference issue? Marking one of them as `u16` is sufficient to fix it.