Enable VDSO on x86_64 statically linked programs [BZ #19767]

Enable VDSO on x86_64 statically linked programs [BZ #19767]

All the required code already existed, and some of it was already
running.

AT_SYSINFO_EHDR is processed if NEED_DL_SYSINFO_DSO is defined, but it
looks like it always is. The call to setup_vdso is also unconditional,
so all that was left to do was setup the function pointers and use
them. This patch just deletes some #ifdef to enable that.

	[BZ #19767]
	* nptl/Makefile (tests-static): Add tst-cond11-static.
	(tests): Likewise.
	* nptl/tst-cond11-static.c: New File.
	* sysdeps/unix/sysv/linux/Makefile (tests-static): Add
	tst-affinity-static.
	(tests): Likewise.
	* sysdeps/unix/sysv/linux/sysdep-vdso.h: Check USE_VSYSCALL
	instead of SHARED.
	* sysdeps/unix/sysv/linux/sysdep.h (ALWAYS_USE_VSYSCALL): New.
	(USE_VSYSCALL): Likewise.
	* sysdeps/unix/sysv/linux/tst-affinity-static.c: New file.
	* sysdeps/unix/sysv/linux/x86/libc-vdso.h: Check USE_VSYSCALL
	instead of SHARED.
	* sysdeps/unix/sysv/linux/x86_64/init-first.c: Don't check
	SHARED.
	* sysdeps/unix/sysv/linux/x86_64/sysdep.h (ALWAYS_USE_VSYSCALL):
	New.