km/spi: activate driver model for SPI flash on KM Kirkwood boards

The corresponding configurations are selected in the common Kconfig file.
This is easier than changing every affected board default configuration
file. The default configuration for the PORTL2 board, however, still needs
some modifications to correctly use the driver model.

Signed-off-by: Pascal Linder <pascal.linder@edu.hefr.ch>
Signed-off-by: Holger Brunck <holger.brunck@ch.abb.com>
Signed-off-by: Stefan Roese <sr@denx.de>
diff --git a/board/keymile/km_arm/Kconfig b/board/keymile/km_arm/Kconfig
index 2542f1e..19c1db3 100644
--- a/board/keymile/km_arm/Kconfig
+++ b/board/keymile/km_arm/Kconfig
@@ -12,6 +12,9 @@
 config BOARD_SPECIFIC_OPTIONS # dummy
 	def_bool y
 	select BOARD_LATE_INIT
+	select DM
+	select DM_SPI
+	select DM_SPI_FLASH
 	imply CMD_CRAMFS
 	imply CMD_DIAG
 	imply FS_CRAMFS