drm/amdgpu: Fix in-tree build

scripts/Makefile.lib isn't found in in-tree build, breaking the
test for whether to take the full path of source files. This
leads to CGLAGS for float and sse instructions not being applied
correctly in the DAL build, which results in build failures.

Instead set AMDKCL_KBUILD_TAKE_PATH=1 directly for in-tree builds.

Signed-off-by: Felix Kuehling <Felix.Kuehling@amd.com>
Reviewed-by: Flora Cui <flora.cui@amd.com>
Reviewed-by: Feifei Xu <Feifei.Xu@amd.com>

drivers/gpu/drm/amd/amdgpu/Makefile

@@ -25,14 +25,15 @@
 
 ifeq (,$(BUILD_AS_DKMS))
 FULL_AMD_PATH=$(srctree)/$(src)/..
+AMDKCL_KBUILD_TAKE_PATH=1
 else
 FULL_AMD_PATH=$(src)/..
-endif
-DISPLAY_FOLDER_NAME=display
-FULL_AMD_DISPLAY_PATH = $(FULL_AMD_PATH)/$(DISPLAY_FOLDER_NAME)
 # commit v5.3-rc4-54-g54b8ae66ae1a
 # kbuild: change *FLAGS_<basetarget>.o to take the path relative to $(obj)
 AMDKCL_KBUILD_TAKE_PATH=$(shell grep -q "target-stem" scripts/Makefile.lib && echo "1" || echo "0")
+endif
+DISPLAY_FOLDER_NAME=display
+FULL_AMD_DISPLAY_PATH = $(FULL_AMD_PATH)/$(DISPLAY_FOLDER_NAME)
 
 ccflags-y := -I$(FULL_AMD_PATH)/include/asic_reg \
 	-I$(FULL_AMD_PATH)/include \