fs/squashfs: Fix index off by 1 for inode SQFS_LDIR_TYPE

I've created a squashfs file system with Yocto (it use squashfs-tools)
and u-boot command sqfsls give the error:'Error while searching inode:
unknown type.'
After some digging in the code I found that the index is off by 1.
This patch fix this issue and I can successful use the sqfsls command.
After search for the squashfs format I found a link talk about a
similar issue but this time in the documentation. The link is:
https://github.com/AgentD/squashfs-tools-ng/commit/e6588526838caece9529

Signed-off-by: Gerard Koskamp <gerard.koskamp@nedap.com>
Tested-by: Joao Marcos Costa <joaomarcos.costa@bootlin.com>
diff --git a/fs/squashfs/sqfs_inode.c b/fs/squashfs/sqfs_inode.c
index 14d70cf..e76ec7c 100644
--- a/fs/squashfs/sqfs_inode.c
+++ b/fs/squashfs/sqfs_inode.c
@@ -49,7 +49,7 @@
 			return sizeof(*ldir);
 
 		di = ldir->index;
-		while (l < i_count + 1) {
+		while (l < i_count) {
 			sz = get_unaligned_le32(&di->size) + 1;
 			index_list_size += sz;
 			di = (void *)di + sizeof(*di) + sz;
@@ -57,7 +57,7 @@
 		}
 
 		return sizeof(*ldir) + index_list_size +
-			(i_count + 1) * SQFS_DIR_INDEX_BASE_LENGTH;
+			i_count * SQFS_DIR_INDEX_BASE_LENGTH;
 	}
 
 	case SQFS_LREG_TYPE: {