PSA test case generation: comment out always-skipped test cases

When we generate a test case for a mechanism that is not implemented,
comment out the test case rather than giving it a never-fulfilled
dependency. That way we don't create test cases that cannot be executed.

Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
diff --git a/scripts/mbedtls_dev/psa_information.py b/scripts/mbedtls_dev/psa_information.py
index 6f9c738..58480fc 100644
--- a/scripts/mbedtls_dev/psa_information.py
+++ b/scripts/mbedtls_dev/psa_information.py
@@ -128,13 +128,13 @@
     def detect_not_implemented_dependencies(self) -> None:
         """Detect dependencies that are not implemented."""
         all_implemented_dependencies = self.read_implemented_dependencies()
-        not_implemented = set()
-        for dep in self.dependencies:
-            if (dep.startswith('PSA_WANT') and
-                    dep not in all_implemented_dependencies):
-                not_implemented.add('DEPENDENCY_NOT_IMPLEMENTED_YET_' + dep)
-        self.dependencies = sorted(not_implemented) + self.dependencies
-        self.dependencies.sort()
+        not_implemented = [dep
+                           for dep in self.dependencies
+                           if (dep.startswith('PSA_WANT') and
+                               dep not in all_implemented_dependencies)]
+        if not_implemented:
+            self.skip_because('not implemented: ' +
+                              ' '.join(not_implemented))
 
     def __init__(self) -> None:
         super().__init__()