Fix build for hikey

* BOARD_BLUETOOTH_BDROID_BUILDCFG_INCLUDE_DIR should be assigned to path
  without quote. hikey assigns to a path with quote, causing its build
  to break after I94cad65c77464e5b467abee05951ddfd35b9f27d

Test: Code compilation
Bug: 32958753
Change-Id: Ia839f606d0079d39ea624a6fccb9f830810556b3
diff --git a/BoardConfigCommon.mk b/BoardConfigCommon.mk
index 58ba88a..18e203d 100644
--- a/BoardConfigCommon.mk
+++ b/BoardConfigCommon.mk
@@ -20,7 +20,7 @@
 ANDROID_ENABLE_RENDERSCRIPT := true
 
 # BT configs
-BOARD_BLUETOOTH_BDROID_BUILDCFG_INCLUDE_DIR := "device/linaro/hikey/bluetooth"
+BOARD_BLUETOOTH_BDROID_BUILDCFG_INCLUDE_DIR := device/linaro/hikey/bluetooth
 BOARD_HAVE_BLUETOOTH := true
 
 # generic wifi