mtd: nand: Add Hisilicon machine dependency

The Hisilicon NAND driver is only needed for a specific
platform, so avoid cluttering the configuration.
Signed-off-by: Ezequiel Garcia <ezequiel@vanguardiasur.com.ar>
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>

drivers/mtd/nand/Kconfig

@@ -542,6 +542,7 @@ config MTD_NAND_SUNXI
 
 config MTD_NAND_HISI504
 	tristate "Support for NAND controller on Hisilicon SoC Hip04"
+	depends on ARCH_HISI || COMPILE_TEST
 	depends on HAS_DMA
 	help
 	  Enables support for NAND controller on Hisilicon SoC Hip04.