mm: update secretmem to use VMA flags on mmap_prepare

mm: update secretmem to use VMA flags on mmap_prepare

This patch updates secretmem to use the new vma_flags_t type which will
soon supersede vm_flags_t altogether.

In order to make this change we also have to update mlock_future_ok(), we
replace the vm_flags_t parameter with a simple boolean is_vma_locked one,
which also simplifies the invocation here.

This is laying the groundwork for eliminating the vm_flags_t in
vm_area_desc and more broadly throughout the kernel.

No functional changes intended.

[lorenzo.stoakes@oracle.com: fix check_brk_limits(), per Chris]
Link: https://lkml.kernel.org/r/3aab9ab1-74b4-405e-9efb-08fc2500c06e@lucifer.local
Link: https://lkml.kernel.org/r/a243a09b0a5d0581e963d696de1735f61f5b2075.1769097829.git.lorenzo.stoakes@oracle.com
Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Cc: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Barry Song <baohua@kernel.org>
Cc: David Hildenbrand <david@kernel.org>
Cc: Dev Jain <dev.jain@arm.com>
Cc: Jason Gunthorpe <jgg@nvidia.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Zi Yan <ziy@nvidia.com>
Cc: Damien Le Moal <dlemoal@kernel.org>
Cc: "Darrick J. Wong" <djwong@kernel.org>
Cc: Jarkko Sakkinen <jarkko@kernel.org>
Cc: Yury Norov <ynorov@nvidia.com>
Cc: Chris Mason <clm@fb.com>
Cc: Pedro Falcato <pfalcato@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>