Add kernel build as a dependency of libbt-vendor

bt_vendor_qcom.c uses 'TIOCPMGET' which is not defined in bionic
ioctl.h,  so if kernel doesn’t build, bt_vendor_qcom.c will have
compilation error. Fixed it by adding a dependency to the make file
of libbt-vendor.

Change-Id: I03550e5e1b4cc945e1e39e39deb27a442a21ddd0
diff --git a/libbt-vendor/Android.mk b/libbt-vendor/Android.mk
index 1867883..8d3f9d4 100644
--- a/libbt-vendor/Android.mk
+++ b/libbt-vendor/Android.mk
@@ -45,6 +45,9 @@
         $(TARGET_OUT_HEADERS)/bt/hci_qcomm_init \
         $(TARGET_OUT_INTERMEDIATES)/KERNEL_OBJ/usr/include
 
+LOCAL_ADDITIONAL_DEPENDENCIES += \
+$(TARGET_OUT_INTERMEDIATES)/KERNEL_OBJ/usr
+
 ifeq ($(BOARD_HAS_QCA_BT_AR3002), true)
 LOCAL_C_FLAGS := \
         -DBT_WAKE_VIA_PROC