resolve merge conflicts of 0bb061f863122431ae70928957a2df221c54b1d6 to master

Change-Id: I0b13f3fc6edcfb2d5982ec13728753906f158c30
diff --git a/wifi/1.5/default/wifi_nan_iface.cpp b/wifi/1.5/default/wifi_nan_iface.cpp
index 84fb558..e2b0332 100644
--- a/wifi/1.5/default/wifi_nan_iface.cpp
+++ b/wifi/1.5/default/wifi_nan_iface.cpp
@@ -534,6 +534,9 @@
 }
 
 void WifiNanIface::invalidate() {
+    if (!isValid()) {
+        return;
+    }
     // send commands to HAL to actually disable and destroy interfaces
     legacy_hal_.lock()->nanDisableRequest(ifname_, 0xFFFF);
     legacy_hal_.lock()->nanDataInterfaceDelete(ifname_, 0xFFFE, "aware_data0");