kleaf: Use kernel-source path as kbuild

Use the kernel-source folder name to hide the kernel version path,
and this folder will be created as symlink. Before building kernel,
the script will build the symlink based on the kernel version of
environment variable. The advantage of this is that there is no need
to change the path whenever the version is updated, and the build
can be switched between different kernel version.

Bug 4344670

Change-Id: Idfc285fee7472bb3d76b6a6cdc1334df5958f4a0
Signed-off-by: Jian-Min Liu <jianminl@nvidia.com>
Reviewed-on: https://git-master.nvidia.com/r/c/linux-nv-oot/+/3158772
Reviewed-by: Laxman Dewangan <ldewangan@nvidia.com>
GVS: buildbot_gerritrpt <buildbot_gerritrpt@nvidia.com>
Reviewed-by: svcacv <svcacv@nvidia.com>

BUILD.bazel

@@ -163,7 +163,7 @@ kernel_module(
         "sound/soc/tegra-virt-alt/snd-soc-tegra-virt-t210ref-pcm.ko",
         "sound/tegra-safety-audio/safety-i2s.ko",
     ],
-    kernel_build = "//android-common-kernel/6.1/kernel-source:tegra_android",
+    kernel_build = "//nvidia-build/kleaf:tegra_android",
     deps = [
         "//hwpm/drivers/tegra/hwpm:hwpm",
     ],

Makefile.kleaf

@@ -10,10 +10,10 @@ export srctree.nvidia-oot := $(abspath $(shell dirname $(lastword $(MAKEFILE_LIS
 endif
 
 ifeq ($(origin srctree.hwpm), undefined)
-export srctree.hwpm := $(KERNEL_SRC)/../../../hwpm
+export srctree.hwpm := $(KERNEL_SRC)/../hwpm
 endif
 
-EXTRA_SYMBOLS += $(O)/../../../hwpm/drivers/tegra/hwpm/Module.symvers
+EXTRA_SYMBOLS += $(OUT_DIR)/../hwpm/drivers/tegra/hwpm/Module.symvers
 
 KERNEL_SRC ?= /lib/modules/$(shell uname -r)/build
 M ?= $(shell pwd)