drm/amdkcl: fix kthread_use_mm/kthread_unuse_mm redefinition

error on sle sp2 server distro with kernel 5.3.18-24

define the kthread_use_mm for kcl only when it is
neither defined in kthread.c nor in mmu_context.h

Signed-off-by: Shiwu Zhang <shiwu.zhang@amd.com>

drivers/gpu/drm/amd/dkms/m4/kthread_use_mm.m4

@@ -3,9 +3,21 @@ dnl # f5678e7f2ac3 kernel: better document the use_mm/unuse_mm API contract
 dnl # 9bf5b9eb232b kernel: move use_mm/unuse_mm to kthread.c
 dnl #
 AC_DEFUN([AC_AMDGPU_KTHREAD_USE_MM], [
-	AC_KERNEL_CHECK_SYMBOL_EXPORT([kthread_use_mm kthread_unuse_mm],
-	[kernel/kthread.c], [
-		AC_DEFINE(HAVE_KTHREAD_USE_MM, 1,
-			[kthread_{use,unuse}_mm() is available])
+	AC_KERNEL_DO_BACKGROUND([
+		dnl #
+		dnl # sle sp2 server distro inlines kthread_use_mm/kthread_unuse_mm
+		dnl # in mmu_context.h
+		dnl #
+		AC_KERNEL_TRY_COMPILE([
+			#include <linux/mm_types.h>
+			#include <linux/kthread.h>
+			#include <linux/mmu_context.h>
+		], [
+			kthread_use_mm(NULL);
+			kthread_unuse_mm(NULL);
+		], [
+			AC_DEFINE(HAVE_KTHREAD_USE_MM, 1,
+				[kthread_{use,unuse}_mm() is available])
+		])
 	])
 ])

include/kcl/kcl_kthread.h

@@ -4,9 +4,7 @@
 
 #include <linux/sched.h>
 #include <linux/kthread.h>
-#ifndef HAVE_KTHREAD_USE_MM
 #include <linux/mmu_context.h>
-#endif
 
 #if !defined(HAVE___KTHREAD_SHOULD_PATK)
 extern bool __kcl_kthread_should_park(struct task_struct *k);