[PAN-2846] Added eea_getPrivacyPrecompileAddress (#1650)

Signed-off-by: Adrian Sutton <adrian.sutton@consensys.net>

docs/Reference/Pantheon-API-Methods.md

@@ -3863,6 +3863,35 @@ are not available.
     The `PRIV` API methods are not enabled by default for JSON-RPC. Use the [`--rpc-http-api`](Pantheon-CLI-Syntax.md#rpc-http-api) 
     or [`--rpc-ws-api`](Pantheon-CLI-Syntax.md#rpc-ws-api) options to enable the `PRIV` API methods.
 
+### priv_getPrivacyPrecompileAddress
+
+Returns the address of the [privacy precompiled contract](../Privacy/Explanation/Private-Transaction-Processing.md). 
+The address is specified by the [`--privacy-precompiled-address`](Pantheon-CLI-Syntax.md#privacy-precompiled-address) command line option. 
+
+**Parameters**
+
+None
+
+**Returns**
+
+`result` : `data` - Address of the privacy precompile 
+
+!!! example 
+    ```bash tab="curl HTTP request"
+    curl -X POST --data '{"jsonrpc":"2.0","method":"priv_getPrivacyPrecompileAddress","params":[], "id":1}' http://127.0.0.1:8545
+    ```
+        
+    ```bash tab="wscat WS request"
+    {"jsonrpc":"2.0","method":"priv_getPrivacyPrecompileAddress","params":[], "id":1}
+    ```
+        
+    ```json tab="JSON result"
+    {
+        "jsonrpc": "2.0",
+        "id": 1,
+        "result": "0x000000000000000000000000000000000000007e"
+    }
+    ```
 
 ### priv_getPrivateTransaction