habanalabs: fix resetting the DRAM BAR

Current code does not takes into account the new DRAM region base
and so calculated address is wrong and can lead to crush.

Signed-off-by: Ohad Sharabi <osharabi@habana.ai>
Reviewed-by: Oded Gabbay <ogabbay@kernel.org>
Signed-off-by: Oded Gabbay <ogabbay@kernel.org>