[Sync EN] ext/ssh2: Fix ssh2_sftp_* return types to include false (realpath, readlink, stat, lstat) (#5640)

Commit: `https://github.com/php/doc-en/commit/cad275c0c1bac225cc295e2ee52ecf2564b6fcda`
PR: `https://github.com/php/doc-en/pull/5640`

**Neue EN-Dateien (noch nicht übersetzt)**
- `reference/ssh2/functions/ssh2-sftp-lstat.xml`
- `reference/ssh2/functions/ssh2-sftp-readlink.xml`
- `reference/ssh2/functions/ssh2-sftp-realpath.xml`
- `reference/ssh2/functions/ssh2-sftp-stat.xml`
