LibArchive: Pass along errors from Tar header checksum validation

Author: https://github.com/timschumi
Commit: cb48b9bc30
Pull-request: https://github.com/SerenityOS/serenity/pull/16241
Reviewed-by: https://github.com/AtkinsSJ
Reviewed-by: https://github.com/sin-ack ✅
Reviewed-by: https://github.com/trflynn89

Userland/Libraries/LibArchive/TarStream.h

@@ -36,7 +36,7 @@ public:
     static ErrorOr<NonnullOwnPtr<TarInputStream>> construct(NonnullOwnPtr<Core::Stream::Stream>);
     ErrorOr<void> advance();
     bool finished() const { return m_stream->is_eof(); }
-    bool valid() const;
+    ErrorOr<bool> valid() const;
     TarFileHeader const& header() const { return m_header; }
     TarFileStream file_contents();