[llvm] [llvm-gsymutil] Print one-time DWO file missing warning under --quiet flag (PR #79882)

[Greg Clayton via llvm-commits]

================
@@ -0,0 +1,13 @@
+#include <iostream>
+#include <unistd.h>
+
+void foo() {
+    std::cout << "This is foo" << std::endl;
+}
+
+int main() {
+    std::cout << "hello world" << std::endl;
+    foo();
+    std::cout << "after foo" << std::endl;
+    return 0;
+}
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clayborg wrote:

Do you even need this file? In your test you are using a `cat` mechanism, so this isn't needed? Either switch your tests to use this file instead of `cat`, or remove the `cat` and use this file.

https://github.com/llvm/llvm-project/pull/79882