drm/amdgpu: fix seq_printf format string

The amdgpu driver has a debugfs interface that shows the amount of
VRAM in use, but the newly added code causes a build error on
all 32-bit architectures:

drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c:1076:17: warning: format '%lu' expects argument of type 'long unsigned int', but argument 4 has type 'long long int' [-Wformat=]

This fixes the format string to use "%llu" for printing 64-bit
numbers, which works everywhere, as long as we also cast to 'u64'.
Unlike atomic64_t, u64 is defined as 'unsigned long long' on
all architectures.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Fixes: a2ef8a97 ("drm/amdgpu: add vram usage into debugfs")
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

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

@@ -1073,10 +1073,10 @@ static int amdgpu_mm_dump_table(struct seq_file *m, void *data)
 	ret = drm_mm_dump_table(m, mm);
 	spin_unlock(&glob->lru_lock);
 	if (ttm_pl == TTM_PL_VRAM)
-		seq_printf(m, "man size:%llu pages, ram usage:%luMB, vis usage:%luMB\n",
+		seq_printf(m, "man size:%llu pages, ram usage:%lluMB, vis usage:%lluMB\n",
 			   adev->mman.bdev.man[ttm_pl].size,
-			   atomic64_read(&adev->vram_usage) >> 20,
-			   atomic64_read(&adev->vram_vis_usage) >> 20);
+			   (u64)atomic64_read(&adev->vram_usage) >> 20,
+			   (u64)atomic64_read(&adev->vram_vis_usage) >> 20);
 	return ret;
 }