qca-nss-drv: Remove legacy wifi code

Mostly for ipq806x platform, reduces overall size by 30%

qca/qca-nss-drv/patches/0013-nss-drv-remove-legacy-wifi.patch

@@ -0,0 +1,30 @@
+--- a/Makefile
++++ b/Makefile
+@@ -352,10 +352,14 @@ endif
+ 
+ ifneq "$(NSS_DRV_WIFIOFFLOAD_ENABLE)" "n"
+ ccflags-y += -DNSS_DRV_WIFIOFFLOAD_ENABLE
++ifeq ($(SoC),$(filter $(SoC),ipq806x))
+ qca-nss-drv-objs += \
+ 			nss_wifi.o \
+ 			nss_wifi_log.o \
+-			nss_wifi_stats.o \
++			nss_wifi_stats.o
++ccflags-y += -DNSS_HAL_IPQ806x_SUPPORT
++endif
++qca-nss-drv-objs += \
+ 			nss_wifi_vdev.o \
+ 			nss_wifili.o \
+ 			nss_wifili_log.o \
+--- a/nss_hal/nss_hal.c
++++ b/nss_hal/nss_hal.c
+@@ -593,7 +593,9 @@ int nss_hal_probe(struct platform_device
+ 	if (npd->wifioffload_enabled == NSS_FEATURE_ENABLED) {
+ 		nss_top->wifi_handler_id = nss_dev->id;
+ 		nss_top->dynamic_interface_table[NSS_DYNAMIC_INTERFACE_TYPE_VAP] = nss_dev->id;
++#if defined(NSS_HAL_IPQ806x_SUPPORT)
+ 		nss_wifi_register_handler();
++#endif
+ 		nss_wifili_register_handler();
+ #ifdef NSS_DRV_WIFI_EXT_VDEV_ENABLE
+ 		nss_wifi_ext_vdev_register_handler();