kernel: Use absolute path for kernel O= argument
The kernel make command is executed in the build root. Without absolute
out paths, kernel out start with "out/" meaning it would be created in
the kernel source. Add BUILD_ROOT to the argument to ensure it's always
made in the actual out/ dir.
Change-Id: I425134a893d4d5c9f31efccaf75e153b5462b76c
diff --git a/build/tasks/kernel.mk b/build/tasks/kernel.mk
index f8670dc..bdef87e 100644
--- a/build/tasks/kernel.mk
+++ b/build/tasks/kernel.mk
@@ -193,7 +193,7 @@
# $(1): output path (The value passed to O=)
# $(2): target to build (eg. defconfig, modules, dtbo.img)
define internal-make-kernel-target
-$(PATH_OVERRIDE) $(KERNEL_MAKE_CMD) $(KERNEL_MAKE_FLAGS) -C $(KERNEL_SRC) O=$(1) ARCH=$(KERNEL_ARCH) $(KERNEL_CROSS_COMPILE) $(KERNEL_CLANG_TRIPLE) $(KERNEL_CC) $(2)
+$(PATH_OVERRIDE) $(KERNEL_MAKE_CMD) $(KERNEL_MAKE_FLAGS) -C $(KERNEL_SRC) O=$(KERNEL_BUILD_OUT_PREFIX)$(1) ARCH=$(KERNEL_ARCH) $(KERNEL_CROSS_COMPILE) $(KERNEL_CLANG_TRIPLE) $(KERNEL_CC) $(2)
endef
# Make a kernel target