Fix NPE restoring socket properties from AS400ConnectionPool reference (#265)

Signed-off-by: Nicola Isotta <[email protected]>

Author: NicolaIsotta

src/main/java/com/ibm/as400/access/AS400ConnectionPool.java

@@ -174,6 +174,9 @@ public AS400ConnectionPool()
                     break;
                 default:
                     if (SocketProperties.isSocketProperty(property)) {
+                        if (socketProperties_ == null) {
+                            socketProperties_ = new SocketProperties();
+                        }
                         socketProperties_.restore(property, value);
                     }
                     break;