Wire readApfPacketFilterData() to the legacy hal

Change-Id: If5d9d3afd40758aea98832e4b350216f496fc3bd
Test: built and flashed, verified boot
diff --git a/wifi/1.2/default/wifi_legacy_hal.h b/wifi/1.2/default/wifi_legacy_hal.h
index dedbbf8..60905ab 100644
--- a/wifi/1.2/default/wifi_legacy_hal.h
+++ b/wifi/1.2/default/wifi_legacy_hal.h
@@ -156,7 +156,7 @@
  * Class that encapsulates all legacy HAL interactions.
  * This class manages the lifetime of the event loop thread used by legacy HAL.
  *
- * Note: aThere will only be a single instance of this class created in the Wifi
+ * Note: There will only be a single instance of this class created in the Wifi
  * object and will be valid for the lifetime of the process.
  */
 class WifiLegacyHal {
@@ -188,6 +188,8 @@
         const std::string& iface_name);
     wifi_error setPacketFilter(const std::string& iface_name,
                                const std::vector<uint8_t>& program);
+    std::pair<wifi_error, std::vector<uint8_t>> readApfPacketFilterData(
+        const std::string& iface_name);
     // Gscan functions.
     std::pair<wifi_error, wifi_gscan_capabilities> getGscanCapabilities(
         const std::string& iface_name);