qcacld-3.0: Kbuild: Remove redundant WLAN_PRE_CAC_INC

In Kbuild the macro WLAN_PRE_CAC_INC is defined twice, with the second
definition overriding the first one. Since the second definition
incorporates the logic from the first definition, the first definition
is pointless, so remove it.

Change-Id: I7e679109b6c08d226236c42c20e18e50537036e9
CRs-Fixed: 3490072

Kbuild

@@ -1696,7 +1696,6 @@ $(call add-wlan-objs,ftm_time_sync,$(FTM_TIME_SYNC_OBJS))
 ########## WLAN PRE_CAC ##########
 
 WLAN_PRE_CAC_DIR := components/pre_cac
-WLAN_PRE_CAC_INC := -I$(WLAN_ROOT)/$(WLAN_PRE_CAC_DIR)/dispatcher/inc
 PRE_CAC_OSIF_DIR := os_if/pre_cac
 WLAN_PRE_CAC_INC := -I$(WLAN_ROOT)/$(WLAN_PRE_CAC_DIR)/dispatcher/inc \
 		  -I$(WLAN_ROOT)/$(PRE_CAC_OSIF_DIR)/inc