Socks5Client: Throw SmackException instead of IOExecption

So that we can wrap the original exception within the
SmackException. It's not possible to wrap it into the IOException
because of the used min Android API level.

smack-extensions/src/main/java/org/jivesoftware/smackx/bytestreams/socks5/Socks5Client.java

@@ -125,8 +125,8 @@ class Socks5Client {
                 }
             }
 
-            // throw generic IO exception if unexpected exception was thrown
-            throw new IOException("Error while connection to SOCKS5 proxy");
+            // throw generic Smack exception if unexpected exception was thrown
+            throw new SmackException("Error while connecting to SOCKS5 proxy", e);
         }
 
     }