configs: drop CONFIG_MMCROOT

CONFIG_MMCROOT is only used to set mmcroot, no need a dedicated macro.

Script as below
"
 for i in `ls include/configs/*.h`
 do
 mmcroot=`sed -n '/define.*MMCROOT/ p' $i  | awk -F\" '{ print $2;}'`

 if [ ! -n "$mmcroot" ]; then
 	continue
 fi

 sed -i '/define.*MMCROOT/ d' $i
 sed -i 's,\" CONFIG_MMCROOT \",'$mmcroot',g' $i

 done
"

Reviewed-by: Fabio Estevam <festevam@denx.de>
Signed-off-by: Peng Fan <peng.fan@nxp.com>
diff --git a/include/configs/imx7-cm.h b/include/configs/imx7-cm.h
index 46ca1c5..2d9f8bb 100644
--- a/include/configs/imx7-cm.h
+++ b/include/configs/imx7-cm.h
@@ -31,7 +31,7 @@
 	"fdt_addr=0x83000000\0" \
 	"mmcdev="__stringify(CONFIG_SYS_MMC_ENV_DEV)"\0" \
 	"mmcpart=1\0" \
-	"mmcroot=" CONFIG_MMCROOT " rootwait rw\0" \
+	"mmcroot=/dev/mmcblk0p2 rootwait rw\0" \
 	"mmcargs=setenv bootargs console=${console},${baudrate} " \
 		"root=${mmcroot}\0" \
 		"loadimage=fatload mmc ${mmcdev}:${mmcpart} ${loadaddr} ${image}\0" \
@@ -83,7 +83,6 @@
 #define CONFIG_SYS_FSL_ESDHC_ADDR       USDHC1_BASE_ADDR
 #define CONFIG_SYS_FSL_USDHC_NUM		2
 
-#define CONFIG_MMCROOT					"/dev/mmcblk0p2"  /* USDHC1 */
 
 /* USB Configs */
 #define CONFIG_MXC_USB_PORTSC  (PORT_PTS_UTMI | PORT_PTS_PTW)