Fix llvm error: variables may be used uninitialized

Signed-off-by: Sergey <sergio_nsk@yahoo.de>
diff --git a/tests/suites/test_suite_psa_crypto.function b/tests/suites/test_suite_psa_crypto.function
index 182443a..36b01ce 100644
--- a/tests/suites/test_suite_psa_crypto.function
+++ b/tests/suites/test_suite_psa_crypto.function
@@ -9672,7 +9672,7 @@
     unsigned char *first_export = NULL;
     unsigned char *second_export = NULL;
     size_t export_size = PSA_EXPORT_KEY_OUTPUT_SIZE(type, bits);
-    size_t first_exported_length;
+    size_t first_exported_length = 0;
     size_t second_exported_length;
 
     if (usage_flags & PSA_KEY_USAGE_EXPORT) {