wifi: fix uninitialized variable

Bug: 149042449
Test: atest VtsHalWifiSupplicantV1_3TargetTest
Change-Id: Ie583d1db3697891c96c9186526ae47f40751b822
diff --git a/wifi/supplicant/1.3/vts/functional/supplicant_sta_network_hidl_test.cpp b/wifi/supplicant/1.3/vts/functional/supplicant_sta_network_hidl_test.cpp
index 93eabd6..6be24bc 100644
--- a/wifi/supplicant/1.3/vts/functional/supplicant_sta_network_hidl_test.cpp
+++ b/wifi/supplicant/1.3/vts/functional/supplicant_sta_network_hidl_test.cpp
@@ -56,6 +56,8 @@
         supplicant_ =
             getSupplicant_1_3(supplicant_v1_3_instance_name_, isP2pOn_);
         EXPECT_TRUE(turnOnExcessiveLogging(supplicant_));
+        sta_iface_ = getSupplicantStaIface_1_3(supplicant_);
+        ASSERT_NE(nullptr, sta_iface_.get());
         sta_network_ = createSupplicantStaNetwork_1_3(supplicant_);
         ASSERT_NE(sta_network_.get(), nullptr);
     }