spi: cadence-xspi: support suspend/resume

spi: cadence-xspi: support suspend/resume

Add system wide suspend and resume support, the suspend hook
implementation is straightforward, just call spi_controller_suspend()
While the resume hook implementation is a bit complex, we need to redo
something which is done during probe, such as enable the interrupts,
setup clk and config the phy for mrvl hw overlay.

Signed-off-by: Jisheng Zhang <jszhang@kernel.org>
Link: https://patch.msgid.link/20260122155119.12865-1-jszhang@kernel.org
Signed-off-by: Mark Brown <broonie@kernel.org>