psa_util: update the documentation of ECC conversion functions

Signed-off-by: Valerio Setti <valerio.setti@nordicsemi.no>
diff --git a/include/mbedtls/psa_util.h b/include/mbedtls/psa_util.h
index e1dd822..a2604e1 100644
--- a/include/mbedtls/psa_util.h
+++ b/include/mbedtls/psa_util.h
@@ -110,9 +110,6 @@
 
 /** Convert an ECC curve identifier from the Mbed TLS encoding to PSA.
  *
- * \note This function is provided solely for the convenience of
- *       Mbed TLS and may be removed at any time without notice.
- *
  * \param grpid         An Mbed TLS elliptic curve identifier
  *                      (`MBEDTLS_ECP_DP_xxx`).
  * \param[out] bits     On success, the bit size of the curve.
@@ -126,9 +123,6 @@
 
 /** Convert an ECC curve identifier from the PSA encoding to Mbed TLS.
  *
- * \note This function is provided solely for the convenience of
- *       Mbed TLS and may be removed at any time without notice.
- *
  * \param curve         A PSA elliptic curve identifier
  *                      (`PSA_ECC_FAMILY_xxx`).
  * \param bits          The bit-length of a private key on \p curve.