staging: android: ion: Call dma_map_sg for syncing and mapping [2/2]

staging: android: ion: Call dma_map_sg for syncing and mapping [2/2]

PD#SWPL-9254

Problem:
uncached display unexpectly.

Solution:
Technically, calling dma_buf_map_attachment should return a buffer
properly dma_mapped. Add calls to dma_map_sg to begin_cpu_access to
ensure this happens. As a side effect, this lets Ion buffers take
advantage of the dma_buf sync ioctls.

Verify:
galilei, franklin

Change-Id: Ib6ca06e59e81031d3c65c2df8824b46baaba6c9f
Signed-off-by: Laura Abbott <labbott@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Jiyu Yang <Jiyu.Yang@amlogic.com>