Don't use INTVARDEF/INTUSE with __libc_enable_secure (bug 14132).

Don't use INTVARDEF/INTUSE with __libc_enable_secure (bug 14132).

Continuing the removal of the obsolete INTDEF / INTVARDEF / INTUSE
mechanism, this patch replaces its use for __libc_enable_secure with
the use of rtld_hidden_data_def and rtld_hidden_proto.

Tested for x86_64 that installed stripped shared libraries are
unchanged by the patch.

	[BZ #14132]
	* elf/dl-sysdep.c (__libc_enable_secure): Use rtld_hidden_data_def
	instead of INTVARDEF.
	(_dl_sysdep_start): Do not use INTUSE with __libc_enable_secure.
	* sysdeps/mach/hurd/dl-sysdep.c (__libc_enable_secure): Use
	rtld_hidden_data_def instead of INTVARDEF.
	(_dl_sysdep_start): Do not use INTUSE with __libc_enable_secure.
	* elf/dl-deps.c (expand_dst): Likewise.
	* elf/dl-load.c (_dl_dst_count): Likewise.
	(_dl_dst_substitute): Likewise.
	(decompose_rpath): Likewise.
	(_dl_init_paths): Likewise.
	(open_path): Likewise.
	(_dl_map_object): Likewise.
	* elf/rtld.c (dl_main): Likewise.
	(process_dl_audit): Likewise.
	(process_envvars): Likewise.
	* include/unistd.h [IS_IN_rtld] (__libc_enable_secure_internal):
	Remove declaration.
	(__libc_enable_secure): Use rtld_hidden_proto.