drm/ttm: Use scnprintf() for avoiding potential buffer overflow

Since snprintf() returns the would-be-output size instead of the
actual output size, the succeeding calls may go beyond the given
buffer limit.  Fix it by replacing with scnprintf().
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Reviewed-by: Huang Rui <ray.huang@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Link: https://patchwork.freedesktop.org/patch/357174/Signed-off-by: Christian König <christian.koenig@amd.com>

drivers/gpu/drm/ttm/ttm_page_alloc_dma.c

@@ -604,7 +604,7 @@ static struct dma_pool *ttm_dma_pool_init(struct device *dev, gfp_t flags,
 	p = pool->name;
 	for (i = 0; i < ARRAY_SIZE(t); i++) {
 		if (type & t[i]) {
-			p += snprintf(p, sizeof(pool->name) - (p - pool->name),
+			p += scnprintf(p, sizeof(pool->name) - (p - pool->name),
 				      "%s", n[i]);
 		}
 	}