spi: spi_amd: Replace ioread/iowrite calls

spi: spi_amd: Replace ioread/iowrite calls

All `ioread*` and `iowrite*` functions are better suited for architecture
independent code to ensure portability across different architectures.
Since AMD SoCs support only the x86 architecture, replacing all `ioread*`
and `iowrite*` calls with `read*` and `write*` calls can reduce the
overhead of ensuring portability and increase the speed of I/O operations.

Co-developed-by: Krishnamoorthi M <krishnamoorthi.m@amd.com>
Signed-off-by: Krishnamoorthi M <krishnamoorthi.m@amd.com>
Co-developed-by: Akshata MukundShetty <akshata.mukundshetty@amd.com>
Signed-off-by: Akshata MukundShetty <akshata.mukundshetty@amd.com>
Signed-off-by: Raju Rangoju <Raju.Rangoju@amd.com>
Link: https://patch.msgid.link/20240925133644.2922359-4-Raju.Rangoju@amd.com
Signed-off-by: Mark Brown <broonie@kernel.org>