kernel.mk: fix building errors on Android 7.0
diff --git a/core/tasks/kernel.mk b/core/tasks/kernel.mk
index 0fcfe0d..76c71aa 100644
--- a/core/tasks/kernel.mk
+++ b/core/tasks/kernel.mk
@@ -8,7 +8,7 @@
 #      http://www.apache.org/licenses/LICENSE-2.0
 #
 
-ifeq ($(KBUILD_OUTPUT),)
+ifneq ($(TARGET_NO_KERNEL),true)
 ifeq ($(TARGET_PREBUILT_KERNEL),)
 
 KERNEL_DIR ?= kernel
@@ -27,7 +27,7 @@
 
 CROSS_COMPILE ?= $(abspath $(TARGET_TOOLS_PREFIX))
 KBUILD_OUTPUT := $(abspath $(TARGET_OUT_INTERMEDIATES)/kernel)
-mk_kernel := + $(hide) $(MAKE) -C $(KERNEL_DIR) O=$(KBUILD_OUTPUT) ARCH=$(TARGET_ARCH) CROSS_COMPILE=$(CROSS_COMPILE) $(if $(SHOW_COMMANDS),V=1)
+mk_kernel := $(hide) $(MAKE) -C $(KERNEL_DIR) O=$(KBUILD_OUTPUT) ARCH=$(TARGET_ARCH) CROSS_COMPILE=$(CROSS_COMPILE) $(if $(SHOW_COMMANDS),V=1)
 
 KERNEL_CONFIG_FILE := $(if $(wildcard $(TARGET_KERNEL_CONFIG)),$(TARGET_KERNEL_CONFIG),$(KERNEL_DIR)/$(KERNEL_CONFIG_DIR)/$(TARGET_KERNEL_CONFIG))
 
@@ -56,17 +56,18 @@
 KERNEL_MODULES_DEP := $(firstword $(wildcard $(TARGET_OUT)/lib/modules/*/modules.dep))
 KERNEL_MODULES_DEP := $(if $(KERNEL_MODULES_DEP),$(KERNEL_MODULES_DEP),$(TARGET_OUT)/lib/modules)
 
-$(TARGET_OUT_INTERMEDIATES)/%.kmodule: $(INSTALLED_KERNEL_TARGET)
-	$(hide) cp -an $(EXTRA_KERNEL_MODULE_PATH_$*) $(TARGET_OUT_INTERMEDIATES)/$*.kmodule
+ALL_EXTRA_MODULES := $(patsubst %,$(TARGET_OUT_INTERMEDIATES)/kmodule/%,$(TARGET_EXTRA_KERNEL_MODULES))
+$(ALL_EXTRA_MODULES): $(TARGET_OUT_INTERMEDIATES)/kmodule/%: $(INSTALLED_KERNEL_TARGET)
 	@echo Building additional kernel module $*
+	$(hide) mkdir -p $(@D) && $(ACP) -fr $(EXTRA_KERNEL_MODULE_PATH_$*) $(@D)
 	$(mk_kernel) M=$(abspath $@) modules
 
-$(KERNEL_MODULES_DEP): $(INSTALLED_KERNEL_TARGET) $(patsubst %,$(TARGET_OUT_INTERMEDIATES)/%.kmodule,$(TARGET_EXTRA_KERNEL_MODULES))
+$(KERNEL_MODULES_DEP): $(INSTALLED_KERNEL_TARGET) $(ALL_EXTRA_MODULES)
 	$(hide) rm -rf $(TARGET_OUT)/lib/modules
 	$(mk_kernel) INSTALL_MOD_PATH=$(abspath $(TARGET_OUT)) modules_install
-	+ $(hide) for kmod in $(TARGET_EXTRA_KERNEL_MODULES) ; do \
+	$(hide) for kmod in $(TARGET_EXTRA_KERNEL_MODULES) ; do \
 		echo Installing additional kernel module $${kmod} ; \
-		$(subst +,,$(subst $(hide),,$(mk_kernel))) INSTALL_MOD_PATH=$(abspath $(TARGET_OUT)) M=$(abspath $(TARGET_OUT_INTERMEDIATES))/$${kmod}.kmodule modules_install ; \
+		$(subst $(hide),,$(mk_kernel)) INSTALL_MOD_PATH=$(abspath $(TARGET_OUT)) M=$(abspath $(TARGET_OUT_INTERMEDIATES))/kmodule/$${kmod} modules_install ; \
 	done
 	$(hide) rm -f $(TARGET_OUT)/lib/modules/*/{build,source}
 endif