smb3: add four dynamic tracepoints for copy_file_range and reflink
Add more dynamic tracepoints to help debug copy_file_range (copychunk)
and clone_range ("duplicate extents"). These are tracepoints for
entering the function and completing without error. For example:
"trace-cmd record -e smb3_copychunk_enter -e smb3_copychunk_done"
or
"trace-cmd record -e smb3_clone_enter -e smb3_clone_done"