Remove unused variables from tests

Fix clang build by removing unused variables and fixing comments
diff --git a/include/mbedtls/ecp.h b/include/mbedtls/ecp.h
index c6e3edb..6bcda17 100644
--- a/include/mbedtls/ecp.h
+++ b/include/mbedtls/ecp.h
@@ -521,7 +521,7 @@
  *                  The output is the group's OID wrapped as ASN.1.
  *
  * \param grp       ECP group used
- * \param buf       Buffer to write to
+ * \param p         Buffer to write to
  * \param size      Buffer size
  * \param olen      Number of bytes written to \c buf
  * \return          0 on success
diff --git a/tests/suites/test_suite_pk.function b/tests/suites/test_suite_pk.function
index 1ad38ea..25c46b2 100644
--- a/tests/suites/test_suite_pk.function
+++ b/tests/suites/test_suite_pk.function
@@ -173,7 +173,6 @@
 #define OPAQUE_MOCK_GOOD_SIGNATURE "good"
 static const unsigned char opaque_mock_hash[8] = "HASHhash";
 static const unsigned char opaque_mock_reference_input[10] = "INPUTinput";
-static const unsigned char opaque_mock_input[10] = "INPUTinput";
 static const unsigned char opaque_mock_reference_encrypted[12] = "C:JOQVUjoqvu";
 static const unsigned char opaque_mock_reference_decrypted[12] = "P:HMOTShmots";
 static char opaque_mock_fake_ctx = 'c';