[BZ #5786]

[BZ #5786]

	* elf/dl-sysdep.c: Undefine ROUND after use.
	* sysdeps/generic/ldsodefs.h [HAVE_DL_DISCOVER_OSVERSION]
	(struct rtld_global_ro): Add _dl_tls_get_addr_soft element.
	* elf/rtld.c (rtld_global_ro): Initialize _dl_discover_osversion.
	* sysdeps/unix/sysv/linux/dl-osinfo.h: Move _dl_discover_osversion
	to ...
	* sysdeps/unix/sysv/linux/dl-sysdep.c: ...here.
	* sysdeps/unix/sysv/linux/dl-sysdep.h: Declare _dl_discover_osversion
	if necessary.
	* sysdeps/unix/sysv/linux/sysconf.c: Handle _SC_ARG_MAX here.