drm/radeon/kms: use RADEON_GPU_PAGE_SIZE instead of 4096

Signed-off-by: Matt Turner <mattst88@gmail.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
diff --git a/drivers/gpu/drm/radeon/radeon.h b/drivers/gpu/drm/radeon/radeon.h
index 3598adc..8b60e36 100644
--- a/drivers/gpu/drm/radeon/radeon.h
+++ b/drivers/gpu/drm/radeon/radeon.h
@@ -276,6 +276,8 @@
 	struct radeon_gart_table_vram	vram;
 };
 
+#define RADEON_GPU_PAGE_SIZE 4096
+
 struct radeon_gart {
 	dma_addr_t			table_addr;
 	unsigned			num_gpu_pages;