Consolidate Linux ftruncate implementations

Consolidate Linux ftruncate implementations

THis patch consolidates all Linux ftruncate implementation on
sysdeps/unix/sysv/linux/ftruncate{64}.c.  It is based on
{INTERNAL,INLINE}_SYSCALL patch [1] to simplify the syscall construction.

General idea is to build ftruncate iff __OFF_T_MATCHES_OFF64_T is not
defined, otherwise ftruncate64 will be build and ftruncate will be an
alias.  The fallocate will use old compat syscall and pass 32-bit off_t
argument, while fallocate64 will handle the correct off64_t passing using
__ALIGNMENT_ARG and SYSCALL_LL64 macros.

Tested on x86_64, i386, aarch64, and armhf.

	* posix/tst-truncate-common.c: New file.
	* posix/tst-truncate.c: Use tst-truncate-common.c.
	* posix/tst-truncate64.c: Likewise and add LFS tests.
	* sysdeps/unix/sysv/linux/arm/ftruncate64.c: Remove file.
	* sysdeps/unix/sysv/linux/generic/wordsize-32/ftruncate.c: Likewise.
	* sysdeps/unix/sysv/linux/generic/wordsize-32/ftruncate64.c: Likewise.
	* sysdeps/unix/sysv/linux/mips/mips32/ftruncate64.c: Likewise.
	* sysdeps/unix/sysv/linux/mips/mips64/ftruncate64.c: Likewise.
	* sysdeps/unix/sysv/linux/powerpc/powerpc32/ftruncate64.c: Likewise.
	* sysdeps/unix/sysv/linux/wordsize-64/ftruncate64.c: Likewise.
	* sysdeps/unix/sysv/linux/ftruncate.c: New file.
	* sysdeps/unix/sysv/linux/ftruncate64.c (__ftruncate64): Use
	INLINE_SYSCALL_CALL, __ALIGNMENT_ARG and SYSCALL_LL64 macros.
	[__OFF_T_MATCHES_OFF64_T] (ftruncate): Add alias.
	* sysdeps/unix/sysv/linux/mips/mips64/syscalls.list (ftruncate):
	Remove.
	* sysdeps/unix/sysv/linux/wordsize-64/syscalls.list (ftruncate):
	Likewise.

[1] https://sourceware.org/ml/libc-alpha/2016-08/msg00646.html