[llvm] [llvm-mca][FeatureRequest] Itimeline graph, note source of delay for each instruction (PR #136423)

[Matt Arsenault via llvm-commits]

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@@ -58,7 +58,14 @@ add  w19, w20, w21
 # CHECK-NEXT: 1.00    -      -      -      -      -      -      -     add	w19, w20, w21
 
 # CHECK:      Timeline view:
-# CHECK-NEXT: Index     01234567
+# CHECK-NEXT: D: Instruction Dispatched
+# CHECK-NEXT: e: Instruction Executingn
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arsenm wrote:

Typo Executingn. Also these are inconsistently capitalizing the second word 

https://github.com/llvm/llvm-project/pull/136423