This patch splits the file arch/x86/vdso-pie.c into machine-dependent
and machine-independent parts by moving the routines vdso_fill_symtable(),
vdso_proxify(), and vdso_remap() to the file pie/vdso.c.

The ARM version of the routines is moved to the source pie/vdso-stub.c
to provide the vDSO proxy stub implementation for architectures
that don't provide the vDSO.
Signed-off-by: Alexander Kartashov <alekskartashov@parallels.com>
Looks-good-to: Cyrill Gorcunov <gorcunov@openvz.org>
Reviewed-by: Christopher Covington <cov@codeaurora.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>