* elf/elf.h (AT_SECURE): New macro.

* elf/elf.h (AT_SECURE): New macro.

	* sysdeps/generic/dl-sysdep.c (_dl_sysdep_start): Grok it,
	set __libc_enable_secure.
	(_dl_show_auxv): Add AT_SECURE to name table.
	* elf/dl-support.c (_dl_aux_init): Grok AT_SECURE, set
	__libc_enable_secure and __libc_enable_secure_decided.
	* sysdeps/unix/sysv/linux/ldsodefs.h
	[__ASSUME_AT_SECURE] (HAVE_AUX_SECURE): Define it.
	* sysdeps/unix/sysv/linux/kernel-features.h
	[__LINUX_KERNEL_VERSION >= 132425] (__ASSUME_AT_SECURE): Define it.