Remove unnecessary try/catch in list_internal_identifiers

The try/catch was used to catch Exceptions and exit with code 1,
a legacy from check_names.py which uses the pattern to exit with
code 2. But code 1 is the default for the Python runtime anyway,
so it is redundant and can be removed.

Signed-off-by: Yuto Takano <yuto.takano@arm.com>
diff --git a/tests/scripts/list_internal_identifiers.py b/tests/scripts/list_internal_identifiers.py
index f18491b..d1b5513 100755
--- a/tests/scripts/list_internal_identifiers.py
+++ b/tests/scripts/list_internal_identifiers.py
@@ -44,21 +44,16 @@
 
     parser.parse_args()
 
-    try:
-        name_check = CodeParser(logging.getLogger())
-        result = name_check.parse_identifiers([
-            "include/mbedtls/*_internal.h",
-            "library/*.h"
-        ])
-        result.sort(key=lambda x: x.name)
+    name_check = CodeParser(logging.getLogger())
+    result = name_check.parse_identifiers([
+        "include/mbedtls/*_internal.h",
+        "library/*.h"
+    ])
+    result.sort(key=lambda x: x.name)
 
-        identifiers = ["{}\n".format(match.name) for match in result]
-        with open("identifiers", "w", encoding="utf-8") as f:
-            f.writelines(identifiers)
-
-    except Exception: # pylint: disable=broad-except
-        traceback.print_exc()
-        sys.exit(1)
+    identifiers = ["{}\n".format(match.name) for match in result]
+    with open("identifiers", "w", encoding="utf-8") as f:
+        f.writelines(identifiers)
 
 if __name__ == "__main__":
     main()