[llvm] [AArch64] C1-Premium SME definitions (PR #212482)

[Nashe Mncube via llvm-commits]

https://github.com/nasherm commented:

```

    I also noticed that for SME load instructions, the resources used are often:

[19.0] - C1PUnitL23
[19.1] - C1PUnitL23
[20]  - C1PUnitLS0
[21]  - C1PUnitLS1

Shouldn't loads be using resource [2]   - C1PUnitCMELD?
```
We model loads/stores on the CME as having a dependency on the load/store units on the main processor. This is a design consideration as we want to illustrate that the main processor will `offload` SME instructions to the CME co-processor. 

https://github.com/llvm/llvm-project/pull/212482