fix kernel-headers build

SVN-Revision: 20584

toolchain/kernel-headers/Makefile

@@ -21,6 +21,7 @@ PKG_SOURCE_URL:=$(LINUX_SITE)
 HOST_BUILD_DIR:=$(KERNEL_BUILD_DIR)/linux-$(LINUX_VERSION)
 PKG_MD5SUM:=$(LINUX_KERNEL_MD5SUM)
 LINUX_DIR := $(HOST_BUILD_DIR)
+FILES_DIR := 
 
 include $(INCLUDE_DIR)/toolchain-build.mk
 include $(INCLUDE_DIR)/kernel-defaults.mk