Do not skip past EOF while reading (#2584)

Do not skip past EOF while reading (#2584)

Make sure to not skip past end of file for better error messages. One
such example is now visible with rar testsuite. You can see the
difference already by an actually not useless use of cat:

```
$ cat .../test_read_format_rar_ppmd_use_after_free.rar | bsdtar -t
bsdtar: Archive entry has empty or unreadable filename ... skipping.
bsdtar: Archive entry has empty or unreadable filename ... skipping.
bsdtar: Truncated input file (needed 119 bytes, only 0 available)
bsdtar: Error exit delayed from previous errors.
```

compared to

```
$ bsdtar -tf .../test_read_format_rar_ppmd_use_after_free.rar
bsdtar: Archive entry has empty or unreadable filename ... skipping.
bsdtar: Archive entry has empty or unreadable filename ... skipping.
bsdtar: Error exit delayed from previous errors.
```

Since the former cannot lseek, the error is a different one
(ARCHIVE_FATAL vs ARCHIVE_EOF). The piped version states explicitly that
truncation occurred, while the latter states EOF because the skip past
the end of file was successful.

Signed-off-by: Tobias Stoeckmann <tobias@stoeckmann.org>