The new API is an exact match for the needs of radeon.

For some reason radeon tries to remove overlapping ranges from the
interval tree, but interval trees (and mmu_interval_notifier_insert())
support overlapping ranges directly. Simply delete all this code.

Since this driver is missing a invalidate_range_end callback, but
still calls get_user_pages(), it cannot be correct against all races.

Link: https://lore.kernel.org/r/20191112202231.3856-8-jgg@ziepe.caReviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>