Wifi: Add support for mapping DSCP to  Wifi AC

This commit adds the needed enum and methods to handle the mapping
of DSCP into wifi access categories.

Bug: 141500691
Bug: 141550272
Test: Builds successfully
Change-Id: I3a85c211057907c2363f7f349d0075e6b4a1b152
diff --git a/wifi/1.4/default/wifi_legacy_hal.h b/wifi/1.4/default/wifi_legacy_hal.h
index 72cf197..c21563e 100644
--- a/wifi/1.4/default/wifi_legacy_hal.h
+++ b/wifi/1.4/default/wifi_legacy_hal.h
@@ -261,6 +261,9 @@
                               wifi_latency_mode mode);
     wifi_error setThermalMitigationMode(wifi_thermal_mode mode,
                                         uint32_t completion_window);
+    wifi_error setDscpToAccessCategoryMapping(uint32_t start, uint32_t end,
+                                              uint32_t access_category);
+    wifi_error resetDscpToAccessCategoryMapping();
     // Logger/debug functions.
     std::pair<wifi_error, uint32_t> getLoggerSupportedFeatureSet(
         const std::string& iface_name);