Add definition of mbedtls_pk_can_do_ext()

Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
diff --git a/include/mbedtls/pk.h b/include/mbedtls/pk.h
index 5225c57..57085de 100644
--- a/include/mbedtls/pk.h
+++ b/include/mbedtls/pk.h
@@ -411,6 +411,27 @@
  */
 int mbedtls_pk_can_do( const mbedtls_pk_context *ctx, mbedtls_pk_type_t type );
 
+#if defined(MBEDTLS_USE_PSA_CRYPTO)
+/**
+ * \brief           Tell if context can do the operation given by PSA algorighm
+ *
+ * \param ctx       The context to query. It must have been initialized.
+ * \param alg       PSA algorithm to check against, the following are allowed:
+ *                  PSA_ALG_RSA_PKCS1V15_SIGN(hash),
+ *                  PSA_ALG_RSA_PSS(hash),
+ *                  PSA_ALG_RSA_PKCS1V15_CRYPT,
+ *                  PSA_ALG_ECDSA(hash),
+ *                  PSA_ALG_ECDH, where hash is a specific hash.
+ *
+ * \return          1 if the context can do operations on the given type.
+ * \return          0 if the context cannot do the operations on the given
+ *                  type. This is always the case for a context that has
+ *                  been initialized but not set up, or that has been
+ *                  cleared with mbedtls_pk_free().
+ */
+int mbedtls_pk_can_do_ext( const mbedtls_pk_context *ctx, psa_algorithm_t alg );
+#endif /* MBEDTLS_USE_PSA_CRYPTO */
+
 /**
  * \brief           Verify signature (including padding if relevant).
  *