spi: spi-geni-qcom: Return error if setup transfer fails

setup_fifo_xfer/setup_gsi_xfer api may fail while transfer
preparation, return error to the client in such case instead
of advancing with the erroneous transfer to prevent unpredictable
transfer scenarios.

Change-Id: Ic02285df53713c813b56d88ad4d6731ace72d54a
Signed-off-by: Vipin Deep Kaur <vkaur@codeaurora.org>
Signed-off-by: Ashish Kori <akori@codeaurora.org>