Adapt to the new key allocation mechanism

diff --git a/include/mbedtls/ssl_internal.h b/include/mbedtls/ssl_internal.h
index 318d13f..fced2cb 100644
--- a/include/mbedtls/ssl_internal.h
+++ b/include/mbedtls/ssl_internal.h
@@ -284,7 +284,7 @@
 #endif
 #if defined(MBEDTLS_KEY_EXCHANGE__SOME__PSK_ENABLED)
 #if defined(MBEDTLS_USE_PSA_CRYPTO)
-    psa_key_slot_t psk_opaque;          /*!< Opaque PSK from the callback   */
+    psa_key_handle_t psk_opaque;        /*!< Opaque PSK from the callback   */
 #endif /* MBEDTLS_USE_PSA_CRYPTO */
     unsigned char *psk;                 /*!<  PSK from the callback         */
     size_t psk_len;                     /*!<  Length of PSK from callback   */