hab: import/export between remote buffer and dmafd

currently hab only supports importing remote buffer
to cpu address, which can't be shared to other process.
Therefore we add dma_buf import/export function in hab

Change-Id: I156c925d7c0cefef5bf146ad8cff38de9c4b3bee
Signed-off-by: Yajun Li <yajunl@codeaurora.org>