ANDROID: mm: Fix __vma_adjust() writes for the maple tree

Only write when necessary to the maple tree.  This should only occur
when the VMA changes.  In the __vma_adjust() case, it is either the vma
when it is expanded, the next vma when the boundary expands into 'vma',
writing the 'insert', or when vma expands/shrinks for shift_arg_pages().

The mas_preallocate() setup should track the intended write to ensure
the correct number of nodes are preallocated for the pending write.

Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Link: http://git.infradead.org/users/jedix/linux-maple.git/commit/61b337f6508fb566553f204a69e743524730e860


[surenb: __vma_adjust was removed in 6.3, therefore these fixes are
not applicable upstream anymore. The patch was obtained from the
author's tree]

Bug: 274059236
Change-Id: I69d68a5b4ff11c40985f7b03b31eec4bb24dcbb6
Signed-off-by: Suren Baghdasaryan <surenb@google.com>