[llvm] [profcheck] Require `unknown` metadata have an origin parameter (PR #157594)

[David Li via llvm-commits]

================
@@ -140,12 +142,38 @@ define void @test() !prof !0 {
 }
 
 !0 = !{!"unknown", i64 123}
-; ON-FUNCTION2: first operand should be 'function_entry_count' or 'synthetic_function_entry_count'
----------------
david-xl wrote:

What happens to this error message (about entry count)?

https://github.com/llvm/llvm-project/pull/157594