test_driver_rsa.c: Fix comment

Signed-off-by: Przemyslaw Stekiel <przemyslaw.stekiel@mobica.com>
diff --git a/tests/src/drivers/test_driver_rsa.c b/tests/src/drivers/test_driver_rsa.c
index b0d9f44..234613e 100644
--- a/tests/src/drivers/test_driver_rsa.c
+++ b/tests/src/drivers/test_driver_rsa.c
@@ -116,7 +116,7 @@
 }
 
 /*
- * opaque versions, to do
+ * opaque versions - TODO
  */
 psa_status_t mbedtls_test_opaque_asymmetric_encrypt(
     const psa_key_attributes_t *attributes, const uint8_t *key,