Return REQUEST_NOT_SUPPORTED if HAL version is below 1.6

Bug: 176932602
Test: verification using system test
Change-Id: Id296991e88ed2656efe5aaa0b2e083c51a116768
diff --git a/src/com/android/phone/PhoneInterfaceManager.java b/src/com/android/phone/PhoneInterfaceManager.java
index 05ed622..f75fd3b 100755
--- a/src/com/android/phone/PhoneInterfaceManager.java
+++ b/src/com/android/phone/PhoneInterfaceManager.java
@@ -861,6 +861,10 @@
                                 request.result =
                                         TelephonyManager
                                                 .ENABLE_NR_DUAL_CONNECTIVITY_RADIO_NOT_AVAILABLE;
+                            } else if (error == CommandException.Error.REQUEST_NOT_SUPPORTED) {
+                                request.result =
+                                        TelephonyManager
+                                                .ENABLE_NR_DUAL_CONNECTIVITY_NOT_SUPPORTED;
                             }
                             loge("enableNrDualConnectivity" + ": CommandException: "
                                     + ar.exception);