ECDH: update comment to reference new test fucntion

Signed-off-by: Manuel Pégourié-Gonnard <[email protected]>

tests/suites/test_suite_ecdh.function

@@ -495,10 +495,8 @@ void ecdh_exchange_calc_secret(int grp_id,
     shared_secret_length = 0;
 
     /* Try again with an output buffer that's larger. */
-    /* Note: this doubles as a weak test for re-using a context. A proper test
-     * for static ECDH with context re-use should also import multiple peer keys
-     * in a row and compute the corresponding shared secrets, but the below is
-     * already better then nothing. */
+    /* Note: this doubles as a weak test for re-using a context.
+     * For a proper test, see ecdh_context_reuse(). */
     TEST_CALLOC(buf, min_buf_size + 1);
     TEST_EQUAL(0,
                mbedtls_ecdh_calc_secret(