[llvm] [AArch64][CostModel] Add SVE bfloat arithmetic tests (NFC) (PR #166951)

[Cullen Rhodes via llvm-commits]

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@@ -1,5 +1,5 @@
 ; NOTE: Assertions have been autogenerated by utils/update_analyze_test_checks.py
-; RUN: opt < %s -enable-no-nans-fp-math -passes="print<cost-model>" -cost-kind=all 2>&1 -disable-output -mtriple=aarch64 -mattr=+fullfp16 -mattr=+sve | FileCheck %s
+; RUN: opt < %s -enable-no-nans-fp-math -passes="print<cost-model>" -cost-kind=all 2>&1 -disable-output -mtriple=aarch64 -mattr=+fullfp16 -mattr=+sve-b16b16 -mattr=+sve | FileCheck %s
----------------
c-rhodes wrote:

-mattr can take more than one feature
```suggestion
; RUN: opt < %s -enable-no-nans-fp-math -passes="print<cost-model>" -cost-kind=all 2>&1 -disable-output -mtriple=aarch64 -mattr=+fullfp16,+sve-b16b16,+sve | FileCheck %s
```

https://github.com/llvm/llvm-project/pull/166951