drm/xe: Add drm_gpusvm_devmem to xe_bo

Add drm_gpusvm_devmem to xe_bo. Required to enable SVM migrations.

Signed-off-by: Matthew Brost <matthew.brost@intel.com>
Reviewed-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Reviewed-by: Himal Prasad Ghimiray <himal.prasad.ghimiray@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20250306012657.3505757-23-matthew.brost@intel.com

drivers/gpu/drm/xe/xe_bo_types.h

@@ -8,6 +8,7 @@
 
 #include <linux/iosys-map.h>
 
+#include <drm/drm_gpusvm.h>
 #include <drm/ttm/ttm_bo.h>
 #include <drm/ttm/ttm_device.h>
 #include <drm/ttm/ttm_placement.h>
@@ -80,6 +81,9 @@ struct xe_bo {
 	 */
 	u16 cpu_caching;
 
+	/** @devmem_allocation: SVM device memory allocation */
+	struct drm_gpusvm_devmem devmem_allocation;
+
 	/** @vram_userfault_link: Link into @mem_access.vram_userfault.list */
 		struct list_head vram_userfault_link;