spi: qcom: geni: set the error code for gpi transfer

Before we invoke spi_finalize_current_transfer() in
spi_gsi_callback_result() we should set the spi->cur_msg->status as
appropriate (0 for success, error otherwise).

The helps to return error on transfer and not wait till it timesout on
error

Signed-off-by: Vinod Koul <vkoul@kernel.org>