spi: nxp-flexspi: Add i.MX platform dependency

This driver also supports various i.MX8 platforms. Add ARCH_MXC for
selecting this driver without Layerscape support.

Fixes: c6b15b2437 ("spi: nxp-flexspi: Fix ARCH_LAYERSCAPE dependency")
Signed-off-by: Alexander Stein <alexander.stein@ew.tq-group.com>
Link: https://lore.kernel.org/r/20230313083621.154729-1-alexander.stein@ew.tq-group.com
Signed-off-by: Mark Brown <broonie@kernel.org>

drivers/spi/Kconfig

@@ -406,7 +406,7 @@ config SPI_HISI_SFC_V3XX
 
 config SPI_NXP_FLEXSPI
 	tristate "NXP Flex SPI controller"
-	depends on ARCH_LAYERSCAPE || COMPILE_TEST
+	depends on ARCH_LAYERSCAPE || ARCH_MXC || COMPILE_TEST
 	depends on HAS_IOMEM
 	help
 	  This enables support for the Flex SPI controller in master mode.