Update ecdh.h

Changs based on review comments
diff --git a/include/mbedtls/ecdh.h b/include/mbedtls/ecdh.h
index 70455e8..922f029 100644
--- a/include/mbedtls/ecdh.h
+++ b/include/mbedtls/ecdh.h
@@ -45,7 +45,7 @@
  */
 typedef enum
 {
-    MBEDTLS_ECDH_OURS, /**< Our key. */
+    MBEDTLS_ECDH_OURS,   /**< Our key. */
     MBEDTLS_ECDH_THEIRS, /**< The key of the peer. */
 } mbedtls_ecdh_side;
 
@@ -101,8 +101,8 @@
  * \see             ecp.h
  *
  * \note            If \p f_rng is not NULL, it is used to implement
- *                  countermeasures against potential elaborate timing
- *                  attacks. For more information, see mbedtls_ecp_mul().
+ *                  countermeasures against side-channel attacks.
+ *                  For more information, see mbedtls_ecp_mul().
  *
  * \param grp       The ECP group.
  * \param z         The destination MPI (shared secret).
@@ -253,8 +253,8 @@
  *                  and servers.
  *
  * \note            If \p f_rng is not NULL, it is used to implement
- *                  countermeasures against potential elaborate timing
- *                  attacks. For more information, see mbedtls_ecp_mul().
+ *                  countermeasures against side-channel attacks.
+ *                  For more information, see mbedtls_ecp_mul().
  *
  * \see             ecp.h
  *