accel/habanalabs: fix SG table creation for dma-buf mapping

In some cases the calculated number of required entries for the dma-buf
SG table is wrong. For example, if the page size is larger than both the
dma max segment size of the importer device and from the exported side,
or if the exported size is part of a phys_pg_pack that is composed of
several pages.
In these cases, redundant entries will be added to the SG table.

Modify the method that the number of entries is calculated, and the way
they are prepared.

Signed-off-by: Tomer Tayar <ttayar@habana.ai>
Reviewed-by: Oded Gabbay <ogabbay@kernel.org>
Signed-off-by: Oded Gabbay <ogabbay@kernel.org>