ARM: imx: Fix incorrect usage of CONFIG_SYS_MMC_ENV_PART

When running the "save" command several times on a mx6qsabresd we see:

U-Boot > save
Saving Environment to MMC...
Writing to MMC(1)... done
U-Boot > save
Saving Environment to MMC...
MMC partition switch failed
U-Boot > save
Saving Environment to MMC...
Writing to MMC(1)... done
U-Boot > save
Saving Environment to MMC...
MMC partition switch failed
U-Boot > save
Saving Environment to MMC...
Writing to MMC(1)... done
U-Boot > save
Saving Environment to MMC...
MMC partition switch failed

This issue is caused by the incorrect usage of CONFIG_SYS_MMC_ENV_PART.

CONFIG_SYS_MMC_ENV_PART should be used to specify the mmc partition that stores
the environment variables.

On some imx boards it is been incorrectly used to pass the partition of kernel
and dtb files for the 'mmcpart' script variable.

Remove the CONFIG_SYS_MMC_ENV_PART usage and configure the 'mmcpart' variable
directly.
Reported-by: NJason Liu <r64343@freescale.com>
Signed-off-by: NFabio Estevam <fabio.estevam@freescale.com>
Acked-by: NJason Liu <r64343@freescale.com>

include/configs/mx53ard.h

@@ -118,7 +118,7 @@
 	"boot_fdt=try\0" \
 	"ip_dyn=yes\0" \
 	"mmcdev=" __stringify(CONFIG_SYS_MMC_ENV_DEV) "\0" \
-	"mmcpart=" __stringify(CONFIG_SYS_MMC_ENV_PART) "\0" \
+	"mmcpart=2\0" \
 	"mmcroot=/dev/mmcblk0p3 rootwait rw\0" \
 	"update_sd_firmware_filename=u-boot.imx\0" \
 	"update_sd_firmware=" \
@@ -240,7 +240,6 @@
 #define CONFIG_ENV_SIZE        (8 * 1024)
 #define CONFIG_ENV_IS_IN_MMC
 #define CONFIG_SYS_MMC_ENV_DEV	0
-#define CONFIG_SYS_MMC_ENV_PART	2
 
 #define CONFIG_OF_LIBFDT
 

include/configs/mx6qsabre_common.h

@@ -97,7 +97,7 @@
 	"fdt_high=0xffffffff\0"	  \
 	"initrd_high=0xffffffff\0" \
 	"mmcdev=" __stringify(CONFIG_SYS_MMC_ENV_DEV) "\0" \
-	"mmcpart=" __stringify(CONFIG_SYS_MMC_ENV_PART) "\0" \
+	"mmcpart=1\0" \
 	"mmcroot=" CONFIG_MMCROOT " rootwait rw\0" \
 	"update_sd_firmware=" \
 		"if test ${ip_dyn} = yes; then " \

include/configs/mx6qsabreauto.h

@@ -35,7 +35,6 @@
 #define CONFIG_SYS_FSL_USDHC_NUM	2
 #if defined(CONFIG_ENV_IS_IN_MMC)
 #define CONFIG_SYS_MMC_ENV_DEV		0
-#define CONFIG_SYS_MMC_ENV_PART		1	/* Boot partition 1 */
 #endif
 
 /* I2C Configs */

include/configs/mx6qsabresd.h

@@ -29,7 +29,6 @@
 #define CONFIG_SYS_FSL_USDHC_NUM	3
 #if defined(CONFIG_ENV_IS_IN_MMC)
 #define CONFIG_SYS_MMC_ENV_DEV		1	/* SDHC3 */
-#define CONFIG_SYS_MMC_ENV_PART		1	/* Boot partition 1 */
 #endif
 
 #endif                         /* __MX6QSABRESD_CONFIG_H */

include/configs/wandboard.h

@@ -118,7 +118,7 @@
 	"boot_fdt=try\0" \
 	"ip_dyn=yes\0" \
 	"mmcdev=" __stringify(CONFIG_SYS_MMC_ENV_DEV) "\0" \
-	"mmcpart=" __stringify(CONFIG_SYS_MMC_ENV_PART) "\0" \
+	"mmcpart=2\0" \
 	"mmcroot=/dev/mmcblk0p3 rootwait rw\0" \
 	"update_sd_firmware_filename=u-boot.imx\0" \
 	"update_sd_firmware=" \
@@ -232,7 +232,6 @@
 #define CONFIG_ENV_IS_IN_MMC
 #define CONFIG_ENV_OFFSET		(6 * 64 * 1024)
 #define CONFIG_SYS_MMC_ENV_DEV		0
-#define CONFIG_SYS_MMC_ENV_PART		2
 
 #define CONFIG_OF_LIBFDT
 #define CONFIG_CMD_BOOTZ