Fixed AlgorithmIdentifier parameters when used with ECDSA signature algorithm in x509 certificate

Signed-off-by: Marek Jansta <jansta@2n.cz>
diff --git a/library/x509write_csr.c b/library/x509write_csr.c
index d792d34..4622d7a 100644
--- a/library/x509write_csr.c
+++ b/library/x509write_csr.c
@@ -363,7 +363,7 @@
     c2 = buf + size;
     MBEDTLS_ASN1_CHK_ADD(sig_and_oid_len,
                          mbedtls_x509_write_sig(&c2, buf + len, sig_oid, sig_oid_len,
-                                                sig, sig_len));
+                                                sig, sig_len, pk_alg));
 
     /*
      * Compact the space between the CSR data and signature by moving the