spi: zynqmp_qspi: Change flush cache to invalidate cache

Before DMA read, ideally cache should be invalidated, so that data from
memory will be updated to cache after DMA is completed. But
flush_dcache_range is being used which is incorrect. Change
flush_dcache_range to invalidate_dcache_range.

Signed-off-by: Ashok Reddy Soma <ashok.reddy.soma@amd.com>
Signed-off-by: Venkatesh Yadav Abbarapu <venkatesh.abbarapu@amd.com>
Link: https://lore.kernel.org/r/20230915031759.28889-2-venkatesh.abbarapu@amd.com


Signed-off-by: Michal Simek <michal.simek@amd.com>