Now that pvclock doesn't require access to the fixmap, all vdso
variants can use it.

The kernel side isn't wired up for 32-bit kernels yet, but this
covers 32-bit and x32 userspace on 64-bit kernels.
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/a7ef693b7a4c88dd2173dc1d4bf6bc27023626eb.1449702533.git.luto@kernel.orgSigned-off-by: Ingo Molnar <mingo@kernel.org>