x86, vdso: Fix size of get_unmapped_area()

The size of the reserved memory for a 32 bit vdso must be the size of the
32 bit vDSO in pages + HPET page + VVAR page.

One page is not enough for this. Grrrr.... silly copy and paste bug,
was right in previous patch.

Signed-off-by: Stefani Seibold <stefani@seibold.net>
Cc: Andy Lutomirski <luto@amacapital.net>
Link: http://lkml.kernel.org/r/1395592694-20571-1-git-send-email-stefani@seibold.net


Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>