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/default/wifi_ap_iface.h b/wifi/1.0/default/wifi_ap_iface.h
index ee5dc56..23d6435 100644
--- a/wifi/1.0/default/wifi_ap_iface.h
+++ b/wifi/1.0/default/wifi_ap_iface.h
@@ -42,11 +42,14 @@
   // HIDL methods exposed.
   Return<void> getName(getName_cb hidl_status_cb) override;
   Return<void> getType(getType_cb hidl_status_cb) override;
+  Return<void> setCountryCode(const hidl_array<int8_t, 2>& code,
+                              setCountryCode_cb hidl_status_cb) override;
 
  private:
   // Corresponding worker functions for the HIDL methods.
   std::pair<WifiStatus, std::string> getNameInternal();
   std::pair<WifiStatus, IfaceType> getTypeInternal();
+  WifiStatus setCountryCodeInternal(const std::array<int8_t, 2>& code);
 
   std::string ifname_;
   std::weak_ptr<legacy_hal::WifiLegacyHal> legacy_hal_;