spi: cadence: Remove Kconfig dependency

Remove Kconfig dependency and enable driver for
all ARCHs.
Also update help description.

Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Acked-by: Sören Brinkmann <soren.brinkmann@xilinx.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

drivers/spi/Kconfig

@@ -159,10 +159,9 @@ config SPI_BUTTERFLY
 
 config SPI_CADENCE
 	tristate "Cadence SPI controller"
-	depends on ARM
 	help
 	  This selects the Cadence SPI controller master driver
-	  used by Xilinx Zynq.
+	  used by Xilinx Zynq and ZynqMP.
 
 config SPI_CLPS711X
 	tristate "CLPS711X host SPI controller"