renameat2: add decoding support

* file.c (decode_renameat, sys_renameat2): New functions.
(sys_renameat): Use decode_renameat.
* pathtrace.c (pathtrace_match): Handle sys_renameat2.
* linux/syscall.h (sys_renameat2): New prototype.
* xlat/rename_flags.in: New file.
4 files changed