spi: spi-xilinx: Fix spi timeout issue with threaded irq enabled

commit a3a5426332dd7b892b31db6ee1ce16af661c7b71 from
https://github.com/Xilinx/linux-xlnx.git

 xlnx_rebase_v5.15

The interrupt handler of the driver currently does a transfer finalize
before disabling the SPI interrupt.  With threaded interrupts enabled this
can allow the SPI core to start a new SPI transfer between the transfer
finalize and the interrupt disable, transfer completion interrupt for the
current transfer will never occur which results in SPI timeout.
This patch fixes the issue by disabling the SPI interrupts before
finalizing the transfer.

Currently we don't have ZynqMP AXI-QSPI setup to test threaded irq usecase.
This fix is validated on customer's ZynqMP AXI-QSPI design.

Signed-off-by: Amit Kumar Mahapatra <amit.kumar-mahapatra@xilinx.com>
Reviewed-by: Radhey Shyam Pandey <radhey.shyam.pandey@amd.com>
State: pending
Signed-off-by: Quanyang Wang <quanyang.wang@windriver.com>