* 'lsfd--error' of https://github.com/masatake/util-linux:
tests: (lsfd) add a case testing ERROR type appeared in TYPE column
tests: (test_mkfds::mmap) new factory
lsfd: add --_drop-prvilege option for testing purpose
lsfd: add ERROR as a new type
lsfd: (refactor) make the steps for new_file consistent
lsfd: (refactor) add abst_class as super class of file_class
lsfd: (refactor) simplify the step to make a file struct
lsfd: (refactor) simplify the step to copy a file struct if the result of its stat is reusable
lsfd: (refactor) flatten bit fields in struct file
lsfd: fix typos of a function name