FP4: Drop unused WIFI_DRIVER_DEFAULT flag

Change-Id: I66bb1324320f08efb58ece18041d4fa7a92eaf1d
diff --git a/BoardConfig.mk b/BoardConfig.mk
index 041b429..815571e 100644
--- a/BoardConfig.mk
+++ b/BoardConfig.mk
@@ -203,7 +203,6 @@
 BOARD_WPA_SUPPLICANT_DRIVER := $(BOARD_HOSTAPD_DRIVER)
 BOARD_WPA_SUPPLICANT_PRIVATE_LIB := $(BOARD_HOSTAPD_PRIVATE_LIB)
 BOARD_WPA_SUPPLICANT_PRIVATE_LIB_EVENT := "ON"
-WIFI_DRIVER_DEFAULT := qca_cld3
 WIFI_DRIVER_STATE_CTRL_PARAM := "/dev/wlan"
 WIFI_DRIVER_STATE_OFF := "OFF"
 WIFI_DRIVER_STATE_ON := "ON"