prima: update WLAN_BLD_DIR for compilation error

This change is to update WLAN_BLD_DIR path to solve the
compilation error.

Change-Id: I7feb9692f2e1e6eee2a72a1a410cca7511ca63aa
CRs-Fixed: 2567463
diff --git a/Kbuild b/Kbuild
index c085b36..508e384 100644
--- a/Kbuild
+++ b/Kbuild
@@ -106,9 +106,9 @@
 endif # ANDROID_BUILD_TOP
 else
 ifneq ($(ANDROID_BUILD_TOP),)
-    WLAN_BLD_DIR := $(ANDROID_BUILD_TOP)/device/qcom/msm8909w/opensource/wlan
+    WLAN_BLD_DIR := $(ANDROID_BUILD_TOP)/device/qcom/sdm429w/opensource/wlan
 else
-    WLAN_BLD_DIR := device/qcom/msm8909w/opensource/wlan
+    WLAN_BLD_DIR := $(BOARD_OPENSOURCE_DIR)/wlan
 endif # ANDROID_BUILD_TOP
 endif # TARGET_SUPPORTS_WEARABLES
 endif # WLAN_PROPRIETARY