[llvm] [Xtensa] Implement Code Density Option. (PR #119639)

[Matt Arsenault via llvm-commits]

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@@ -0,0 +1,17 @@
+# RUN: not llvm-mc -triple xtensa --mattr=+density %s 2>&1 | FileCheck %s
+
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arsenm wrote:

I mean just leave it in test/MC/Xtensa 

https://github.com/llvm/llvm-project/pull/119639