CRISv32: Select MTDRAM for axisflashmap

Fixes compile error on allmodconfig.

Signed-off-by: Jesper Nilsson <jesper.nilsson@axis.com>
diff --git a/arch/cris/arch-v32/drivers/Kconfig b/arch/cris/arch-v32/drivers/Kconfig
index 6792503..6880f94 100644
--- a/arch/cris/arch-v32/drivers/Kconfig
+++ b/arch/cris/arch-v32/drivers/Kconfig
@@ -109,6 +109,7 @@
 	select MTD_JEDECPROBE
 	select MTD_BLOCK
 	select MTD_COMPLEX_MAPPINGS
+	select MTD_MTDRAM
 	help
 	  This option enables MTD mapping of flash devices.  Needed to use
 	  flash memories.  If unsure, say Y.