Rename get_pk_type_and_md_alg

The function is for both tls12 and tls13 now.

Signed-off-by: Jerry Yu <jerry.h.yu@arm.com>
diff --git a/library/ssl_tls12_client.c b/library/ssl_tls12_client.c
index 47557ae..3ac17ce 100644
--- a/library/ssl_tls12_client.c
+++ b/library/ssl_tls12_client.c
@@ -2359,7 +2359,7 @@
          */
         MBEDTLS_SSL_CHK_BUF_READ_PTR( p, end, 2 );
         sig_alg = MBEDTLS_GET_UINT16_BE( p, 0 );
-        if( mbedtls_ssl_tls13_get_pk_type_and_md_alg_from_sig_alg(
+        if( mbedtls_ssl_get_pk_type_and_md_alg_from_sig_alg(
                                             sig_alg, &pk_alg, &md_alg ) != 0 &&
             ! mbedtls_ssl_sig_alg_is_offered( ssl, sig_alg ) &&
             ! mbedtls_ssl_sig_alg_is_supported( ssl, sig_alg ) )