Convert CONFIG_MTD_PARTITIONS et al to Kconfig

This converts the following to Kconfig:
   CONFIG_MTD_PARTITIONS
   CONFIG_MTD_DEVICE

Signed-off-by: Adam Ford <aford173@gmail.com>
diff --git a/configs/display5_defconfig b/configs/display5_defconfig
index 1f3007f..2a85cf1 100644
--- a/configs/display5_defconfig
+++ b/configs/display5_defconfig
@@ -59,6 +59,8 @@
 CONFIG_SYS_BOOTCOUNT_SINGLEWORD=y
 CONFIG_SYS_BOOTCOUNT_ADDR=0x020CC068
 CONFIG_FSL_ESDHC=y
+CONFIG_MTD_DEVICE=y
+CONFIG_MTD_PARTITIONS=y
 CONFIG_SPI_FLASH=y
 CONFIG_SPI_FLASH_BAR=y
 CONFIG_SPI_FLASH_SPANSION=y