mtd: denali: add Kconfig dependency

Signed-off-by: Karl Beldan <karl.beldan@gmail.com>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
diff --git a/drivers/mtd/nand/Kconfig b/drivers/mtd/nand/Kconfig
index 4d4066f..1d69920 100644
--- a/drivers/mtd/nand/Kconfig
+++ b/drivers/mtd/nand/Kconfig
@@ -60,6 +60,7 @@
 config MTD_NAND_DENALI_SCRATCH_REG_ADDR
         hex "Denali NAND size scratch register address"
         default "0xFF108018"
+        depends on MTD_NAND_DENALI
         help
           Some platforms place the NAND chip size in a scratch register
           because (some versions of) the driver aren't able to automatically