[clang] [HIP][SPIRV] Enable the SPIRV backend instead of the translator through an experimental flag. (PR #162282)

[Manuel Carrasco via cfe-commits]

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@@ -0,0 +1,12 @@
+// This test case validates the behavior of -use-experimental-spirv-backend
+
+// Test that -use-experimental-spirv-backend calls clang -cc1 with the SPIRV triple.
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mgcarrasco wrote:

Now we have the test cases for `-ccc-print-bindings` and `-ccc-print-phases`

https://github.com/llvm/llvm-project/pull/162282