Convert CONFIG_CMD_EECONFIG to Kconfig

This converts the following to Kconfig:
   CONFIG_CMD_EECONFIG

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/board/gateworks/gw_ventana/Kconfig b/board/gateworks/gw_ventana/Kconfig
index ccce98e..c577984 100644
--- a/board/gateworks/gw_ventana/Kconfig
+++ b/board/gateworks/gw_ventana/Kconfig
@@ -9,4 +9,9 @@
 config SYS_CONFIG_NAME
 	default "gw_ventana"
 
+config CMD_EECONFIG
+	bool "Enable the 'econfig' command"
+	help
+	  Provides access to EEPROM configuration on Gateworks Ventana
+
 endif
diff --git a/configs/gwventana_emmc_defconfig b/configs/gwventana_emmc_defconfig
index d638f8b..5629dc6 100644
--- a/configs/gwventana_emmc_defconfig
+++ b/configs/gwventana_emmc_defconfig
@@ -4,6 +4,7 @@
 CONFIG_SPL_LIBCOMMON_SUPPORT=y
 CONFIG_SPL_LIBGENERIC_SUPPORT=y
 CONFIG_TARGET_GW_VENTANA=y
+CONFIG_CMD_EECONFIG=y
 CONFIG_SPL_MMC_SUPPORT=y
 CONFIG_SPL_SERIAL_SUPPORT=y
 CONFIG_SPL_WATCHDOG_SUPPORT=y
diff --git a/configs/gwventana_gw5904_defconfig b/configs/gwventana_gw5904_defconfig
index 0aef36a..49566ce 100644
--- a/configs/gwventana_gw5904_defconfig
+++ b/configs/gwventana_gw5904_defconfig
@@ -4,6 +4,7 @@
 CONFIG_SPL_LIBCOMMON_SUPPORT=y
 CONFIG_SPL_LIBGENERIC_SUPPORT=y
 CONFIG_TARGET_GW_VENTANA=y
+CONFIG_CMD_EECONFIG=y
 CONFIG_SPL_MMC_SUPPORT=y
 CONFIG_SPL_SERIAL_SUPPORT=y
 CONFIG_SPL_WATCHDOG_SUPPORT=y
diff --git a/configs/gwventana_nand_defconfig b/configs/gwventana_nand_defconfig
index 85c3485..982a62e 100644
--- a/configs/gwventana_nand_defconfig
+++ b/configs/gwventana_nand_defconfig
@@ -4,6 +4,7 @@
 CONFIG_SPL_LIBCOMMON_SUPPORT=y
 CONFIG_SPL_LIBGENERIC_SUPPORT=y
 CONFIG_TARGET_GW_VENTANA=y
+CONFIG_CMD_EECONFIG=y
 CONFIG_SPL_MMC_SUPPORT=y
 CONFIG_SPL_SERIAL_SUPPORT=y
 CONFIG_SPL_NAND_SUPPORT=y
diff --git a/include/configs/gw_ventana.h b/include/configs/gw_ventana.h
index ba06fb6..0fcbdf9 100644
--- a/include/configs/gw_ventana.h
+++ b/include/configs/gw_ventana.h
@@ -142,7 +142,6 @@
 /* Various command support */
 #define CONFIG_CMD_HDMIDETECT    /* detect HDMI output device */
 #define CONFIG_CMD_GSC
-#define CONFIG_CMD_EECONFIG      /* Gateworks EEPROM config cmd */
 #define CONFIG_CMD_UNZIP         /* gzwrite */
 #define CONFIG_RBTREE
 
diff --git a/include/configs/pcm058.h b/include/configs/pcm058.h
index f622be6..041d840 100644
--- a/include/configs/pcm058.h
+++ b/include/configs/pcm058.h
@@ -88,7 +88,6 @@
 /* Various command support */
 #define CONFIG_CMD_HDMIDETECT    /* detect HDMI output device */
 #define CONFIG_CMD_GSC
-#define CONFIG_CMD_EECONFIG      /* Gateworks EEPROM config cmd */
 #define CONFIG_RBTREE
 
 /* Physical Memory Map */
diff --git a/scripts/config_whitelist.txt b/scripts/config_whitelist.txt
index 0eb7c2a..094c41f 100644
--- a/scripts/config_whitelist.txt
+++ b/scripts/config_whitelist.txt
@@ -383,7 +383,6 @@
 CONFIG_CMDLINE_EDITING
 CONFIG_CMDLINE_PS_SUPPORT
 CONFIG_CMDLINE_TAG
-CONFIG_CMD_EECONFIG
 CONFIG_CMD_EEPROM
 CONFIG_CMD_EEPROM_LAYOUT
 CONFIG_CMD_ENTERRCM