mm/cma_debug.c: align the name buffer length as struct cma

Avoids truncating the debugfs output to 16 chars.  Potentially alters
the userspace output, but this is a debugfs interface and there are no
stability guarantees.

Link: https://lkml.kernel.org/r/20220719091554.27864-1-quic_yingangl@quicinc.com
Signed-off-by: Kassey Li <quic_yingangl@quicinc.com>
Cc: Sasha Levin <sashal@kernel.org>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Minchan Kim <minchan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

Author: Kassey Li

mm/cma_debug.c

@@ -163,7 +163,7 @@ DEFINE_DEBUGFS_ATTRIBUTE(cma_alloc_fops, NULL, cma_alloc_write, "%llu\n");
 static void cma_debugfs_add_one(struct cma *cma, struct dentry *root_dentry)
 {
 	struct dentry *tmp;
-	char name[16];
+	char name[CMA_MAX_NAME];
 
 	scnprintf(name, sizeof(name), "cma-%s", cma->name);