drm/amdgpu: add header file for macro SZ_1M

Fixes: 4dee6e4c ("drm/amdgpu: use linux size macro to simplify ONE_Kib & One_Mib")
Signed-off-by: Flora Cui <flora.cui@amd.com>
Reviewed-by: Kevin Wang <kevin1.wang@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c

@@ -41,6 +41,7 @@
 #include <linux/swap.h>
 #include <linux/swiotlb.h>
 #include <linux/dma-buf.h>
+#include <linux/sizes.h>
 
 #include <drm/ttm/ttm_bo_api.h>
 #include <drm/ttm/ttm_bo_driver.h>