Define FALLOC_FL_INSERT_RANGE, FALLOC_FL_UNSHARE_RANGE in bits/fcntl-linux.h

[Florian Weimer]

* Joseph Myers:

> 2016-12-14  Joseph Myers  <joseph@codesourcery.com>
>
> 	* sysdeps/unix/sysv/linux/bits/fcntl-linux.h [__USE_GNU]: Include
> 	<linux/falloc.h>.
> 	(FALLOC_FL_KEEP_SIZE): Remove.
> 	(FALLOC_FL_PUNCH_HOLE): Likewise.
> 	(FALLOC_FL_COLLAPSE_RANGE): Likewise.
> 	(FALLOC_FL_ZERO_RANGE): Likewise.

Looks good to me.