docs: update mTLS support in ApisixTls reference (#624)
Signed-off-by: Jintao Zhang <zhangjintao9020@gmail.com>
diff --git a/docs/en/latest/references/apisix_tls.md b/docs/en/latest/references/apisix_tls.md
index 3e46214..0d2f5d8 100644
--- a/docs/en/latest/references/apisix_tls.md
+++ b/docs/en/latest/references/apisix_tls.md
@@ -21,9 +21,14 @@
#
-->
-| Field | Type | Description |
-|---------------|----------|---------------------------------|
-| hosts | array | The domain list to identify which hosts (matched with SNI) can use the TLS certificate stored in the Secret. |
-| secret | object | The definition of the related Secret object with current ApisixTls object. |
-| name | string | The name of secret, the secret contains key and cert for `TLS`. |
-| namespace | string | The namespace of secret, the secret contains key and cert for `TLS`. |
+| Field | Type | Description |
+|-------------------------------|----------|---------------------------------------------------------------------------------------------------------------|
+| hosts | array | The domain list to identify which hosts (matched with SNI) can use the TLS certificate stored in the Secret. |
+| secret | object | The definition of the related Secret object with current ApisixTls object. |
+| secret.name | string | The name of the related Secret object with current ApisixTls object. |
+| secret.namespace | string | The namespace of the related Secret object with current ApisixTls object. |
+| client | object | The configuration of the certificate provided by the client. |
+| client.caSecret | object | The definition of the related Secret object with the certificate provided by the client. |
+| client.caSecret.name | string | The name of the related Secret object with the certificate provided by the client. |
+| client.caSecret.namespace | string | The namespace of the related Secret object with the certificate provided by the client. |
+| client.depth | int | The max certificate of chain length. |
