[llvm] [Bazel] Add llvm-mca unittests (PR #90309)

[Aiden Grossman via llvm-commits]

================
@@ -3111,12 +3111,26 @@ cc_library(
 )
 
 cc_library(
-    name = "llvm-mca-headers",
+    name = "MCAApplication",
----------------
boomanaiden154 wrote:

Not sure this is the best name for this library. Open to suggestions. We can't just do what is done for `llvm-exegesis` as `MCA` is already taken by the actual MCA library, so it needs to be something else.

https://github.com/llvm/llvm-project/pull/90309