Convert CONFIG_CMD_IDE to Kconfig

This converts the following to Kconfig:
   CONFIG_CMD_IDE

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/configs/M54455EVB_a66_defconfig b/configs/M54455EVB_a66_defconfig
index 3aed04e..d681d32 100644
--- a/configs/M54455EVB_a66_defconfig
+++ b/configs/M54455EVB_a66_defconfig
@@ -3,6 +3,7 @@
 CONFIG_TARGET_M54455EVB=y
 CONFIG_SYS_EXTRA_OPTIONS="SYS_ATMEL_BOOT,SYS_INPUT_CLKSRC=66666666"
 CONFIG_BOOTDELAY=1
+CONFIG_CMD_IDE=y
 # CONFIG_CMD_LOADB is not set
 # CONFIG_CMD_LOADS is not set
 CONFIG_CMD_SF=y