fix broken JPEG loading. Issue #40001

(cherry picked from commit d9f5c47d2a9730b4b5cc6d7059b069cd0867414e)

packages/pasjpeg/src/jdmarker.pas

@@ -1747,6 +1747,7 @@ begin
       datasrc^.next_input_byte := next_input_byte;
       datasrc^.bytes_in_buffer := bytes_in_buffer;
       cinfo^.src^.skip_input_data(cinfo, long(Offset-headerlen));
+      Dec(remaining, long(Offset-headerlen));
       next_input_byte := datasrc^.next_input_byte;
       bytes_in_buffer := datasrc^.bytes_in_buffer;
     end;