[llvm] [AVR] Wrap out-of-bounds relative jumps (PR #118015)

[Michael Büsch via llvm-commits]

mbuesch wrote:

Does this fix `attiny26`, too?

I get this
```
error: out of range branch target (expected an integer in the range -4096 to 4095)
```
with the nightly rust compiler on an `attiny26` target, too.

Would this change fix this, even though it doesn't apply `FeatureWrappingRjmp` to `attiny26`?

https://github.com/llvm/llvm-project/pull/118015