Fix get_user_pages() autoconf test for 4.4.y kernel

Fix get_user_pages() autoconf test for 4.4.y kernel

The following kernel commit has been back-ported to linux-4.4.y kernel:

    commit 8e50b8b07f462ab4b91bc1491b1c91bd75e4ad40
    Author: Lorenzo Stoakes <lstoakes@gmail.com>
    Date:   Thu Oct 13 01:20:16 2016 +0100

	mm: replace get_user_pages() write/force parameters with gup_flags

	commit 768ae309a96103ed02eb1e111e838c87854d8b51 upstream.

	This removes the 'write' and 'force' from get_user_pages() and replaces
	them with 'gup_flags' to make the use of FOLL_FORCE explicit in callers
	as use of this flag can result in surprising behaviour (and hence bugs)
	within the mm subsystem.

And it changes the function signature of get_user_pages(), so introduce
an extra flag STAPCONF_GET_USER_PAGES_FLAGS and the corresponding test program
to fix it.

Signed-off-by: Hou Tao <houtao1@huawei.com>