changelog: improve wording

Signed-off-by: Valerio Setti <valerio.setti@nordicsemi.no>
diff --git a/ChangeLog.d/7764.txt b/ChangeLog.d/7764.txt
index 0734fb9..9830584 100644
--- a/ChangeLog.d/7764.txt
+++ b/ChangeLog.d/7764.txt
@@ -1,4 +1,4 @@
 Features
    * Add functions mbedtls_ecc_group_to_psa() and mbedtls_ecc_group_from_psa()
      to convert between mbedtls_ecp_group_id and psa_ecc_family_t and curve's
-     bit size and vice versa, respectively.
+     bit size.