VMCI: Avoid extra check for access_ok()

get_user_pages_fast() is already having a check for the same. This
double check can be removed.

Signed-off-by: Souptick Joarder <jrdr.linux@gmail.com>
Link: https://lore.kernel.org/r/1588709912-8065-1-git-send-email-jrdr.linux@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>