wifi(implementation): Use stub for |read_packet_filter|

Use the stub to take care of vendors who don't implement the new HAL
functionality.

Note: This is just an internal cleanup to be consistent with other
functions.

Bug: 73804303
Test: Compiles
Change-Id: I393194772f35a3620c5acd4d5c3b5a6d072cd507
diff --git a/wifi/1.2/default/wifi_legacy_hal.cpp b/wifi/1.2/default/wifi_legacy_hal.cpp
index c314e64..375204c 100644
--- a/wifi/1.2/default/wifi_legacy_hal.cpp
+++ b/wifi/1.2/default/wifi_legacy_hal.cpp
@@ -494,10 +494,6 @@
 
 std::pair<wifi_error, std::vector<uint8_t>>
 WifiLegacyHal::readApfPacketFilterData(const std::string& iface_name) {
-    if (global_func_table_.wifi_read_packet_filter == nullptr) {
-        return {WIFI_ERROR_NOT_SUPPORTED, {}};
-    }
-
     PacketFilterCapabilities caps;
     wifi_error status = global_func_table_.wifi_get_packet_filter_capabilities(
         getIfaceHandle(iface_name), &caps.version, &caps.max_len);
diff --git a/wifi/1.2/default/wifi_legacy_hal_stubs.cpp b/wifi/1.2/default/wifi_legacy_hal_stubs.cpp
index 24aaf15..fc28bb5 100644
--- a/wifi/1.2/default/wifi_legacy_hal_stubs.cpp
+++ b/wifi/1.2/default/wifi_legacy_hal_stubs.cpp
@@ -130,6 +130,7 @@
     populateStubFor(&hal_fn->wifi_nan_data_end);
     populateStubFor(&hal_fn->wifi_get_packet_filter_capabilities);
     populateStubFor(&hal_fn->wifi_set_packet_filter);
+    populateStubFor(&hal_fn->wifi_read_packet_filter);
     populateStubFor(&hal_fn->wifi_get_roaming_capabilities);
     populateStubFor(&hal_fn->wifi_enable_firmware_roaming);
     populateStubFor(&hal_fn->wifi_configure_roaming);