Add missed FUSE operations

[ligurio]

https://libfuse.github.io/doxygen/structfuse__operations.html

[ligurio]

Missed (in comparison with [1] and [2]):

• lseek(), not available in FUSE_USE_VERSION == 29
• copy_file_range(), not available in FUSE_USE_VERSION == 29
• poll(), not available in FUSE_USE_VERSION == 29
• utimens()

Don't forget to update manual page.

1. https://libfuse.github.io/doxygen/structfuse__operations.html#a2c02838d30391c09dd5213edc61e106a
2. https://github.com/libfuse/libfuse/blob/master/example/passthrough.c
3. https://github.com/libfuse/libfuse/blob/master/example/passthrough.c#L447-L487

[ligurio]

Actually missed only utimens(), others looks unsupported in FUSE 2.9.