wifi: Fixing Nits

Changes in the CL to fix bugs found while integrating
with framework:
1. Added IWifiApIface.setCountryCode()
Bug: 34682168
2. Fixed documentation nits in .hal files.
Bug: 34468218
3. Changed roaming state enum values.
Bug: 34715231
4. Added log for EBUSY in legacyErrorToString()
Bug: 34715469
5. Remove "-Wno-unused parameter" from Android.mk
Bug: 34611289
6. Remove the erroneous |onFailure| callback invocation in wifi.cpp.
7. Add null terminations to strings passed to legacy HAL API's
8. Remove unused |IWifiStaIface.stopDebugPacketFateMonitoring|.

Test: Compiles
Change-Id: If3a3e2f360a378c59dc56b8bbe3a0c6d400b3bd8
diff --git a/wifi/1.0/IWifiStaIface.hal b/wifi/1.0/IWifiStaIface.hal
index 6a738a9..2c72ead 100644
--- a/wifi/1.0/IWifiStaIface.hal
+++ b/wifi/1.0/IWifiStaIface.hal
@@ -439,7 +439,8 @@
 
   /**
    * API to start packet fate monitoring.
-   * - Once stared, monitoring must remain active until HAL is unloaded.
+   * - Once started, monitoring must remain active until HAL is stopped or the
+   *   chip is reconfigured.
    * - When HAL is unloaded, all packet fate buffers must be cleared.
    * - The packet fates are used to monitor the state of packets transmitted/
    *   received during association.
@@ -455,20 +456,6 @@
   startDebugPacketFateMonitoring() generates (WifiStatus status);
 
   /**
-   * API to stop packet fate monitoring.
-   *
-   * @return status WifiStatus of the operation.
-   *         Possible status codes:
-   *         |WifiStatusCode.SUCCESS|,
-   *         |WifiStatusCode.ERROR_WIFI_IFACE_INVALID|,
-   *         |WifiStatusCode.ERROR_NOT_SUPPORTED|,
-   *         |WifiStatusCode.ERROR_NOT_STARTED|,
-   *         |WifiStatusCode.ERROR_NOT_AVAILABLE|,
-   *         |WifiStatusCode.ERROR_UNKNOWN|
-   */
-  stopDebugPacketFateMonitoring() generates (WifiStatus status);
-
-  /**
    * API to retrieve fates of outbound packets.
    * - HAL implementation must return the fates of
    *   all the frames transmitted for the most recent association.