Allow Invoking `zstd --list` When `stdin` is not a `tty`
Allow Invoking `zstd --list` When `stdin` is not a `tty`

Also now returns an error when no inputs are given.

New proposed behavior:

```
felix@odin:~/prog/zstd (list-stdin-check)$ ./zstd -l; echo $?
No files given
1
felix@odin:~/prog/zstd (list-stdin-check)$ ./zstd -l Makefile.zst; echo $?
Frames  Skips  Compressed  Uncompressed  Ratio  Check  Filename
     1      0     3.08 KB      10.92 KB  3.544  XXH64  Makefile.zst
0
felix@odin:~/prog/zstd (list-stdin-check)$ ./zstd -l <Makefile.zst; echo $?
zstd: --list does not support reading from standard input
No files given
1
felix@odin:~/prog/zstd (list-stdin-check)$ ./zstd -l Makefile.zst <Makefile.zst; echo $?
Frames  Skips  Compressed  Uncompressed  Ratio  Check  Filename
     1      0     3.08 KB      10.92 KB  3.544  XXH64  Makefile.zst
0
felix@odin:~/prog/zstd (list-stdin-check)$
```

Cyan4973/zstd,Cyan4973/zstd,Cyan4973/zstd,Cyan4973/zstd,Cyan4973/zstd