Replace cdf! macro with const fns

Notable changes:

cdf! always required the parameter count to be == CDF_LEN - 1, the new cdf function accepts any parameter count < CDF_LEN. Any values after the last parameter will be zero. (e.g. if the output has a length of 8 and the parameter count is 5, then the output values 6 to 8 will be zero). This means:
```
let test: [u16; 4] = cdf!(123); // Error: Number of parameters must be exactly (4 - 1)
let test: [u16; 4] = cdf([123]); // Works: test == [some_value, 0, 0, 0]
```
Added helper functions for multi-dimensional arrays (up to 5D) to avoid spamming the cdf macro/fn
```
[
cdf!(123, 456, 789),
cdf!(987, 654, 321),
// ...
]
```
will become
```
cdf_2d([
[123, 456, 789],
[987, 654, 321],
// ...
])
```
and so on.
Check all input parameters to be in the range [0, 32768] to avoid underflows in 32768 - val
Fully replaced macro with generic code. Type safety is ensured through the function signatures and compile-time assert! statements

The code for cdf_2d, cdf_3d etc. is a little messy. But it's the best way I found to keep these const without some sort of macroized implementation (which seems a bit overkill for just 5 similar functions).

xiph / rav1e

Replace cdf! macro with const fns #3334

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