Remove CONFIG_SYS_MMC_IMG_LOAD_PART from CONFIG namespace

This option is used as part of configuring the default environment for a
number of platforms.  However, it is always set to 1 and the only time
it is part of Kconfig, it is used in a hard-coded manner.  Hard-code the
value in the environment instead.

Signed-off-by: Tom Rini <trini@konsulko.com>
diff --git a/include/configs/imx8mq_phanbell.h b/include/configs/imx8mq_phanbell.h
index 54922b8..7afdfd6 100644
--- a/include/configs/imx8mq_phanbell.h
+++ b/include/configs/imx8mq_phanbell.h
@@ -60,7 +60,7 @@
 	"initrd_addr=0x43800000\0"		\
 	"initrd_high=0xffffffffffffffff\0" \
 	"mmcdev="__stringify(CONFIG_SYS_MMC_ENV_DEV)"\0" \
-	"mmcpart=" __stringify(CONFIG_SYS_MMC_IMG_LOAD_PART) "\0" \
+	"mmcpart=1\0" \
 	"mmcroot=" CONFIG_MMCROOT " rootwait rw\0" \
 	"mmcautodetect=yes\0" \
 	"mmcargs=setenv bootargs console=${console} root=${mmcroot}\0 " \
@@ -132,6 +132,4 @@
 #define CONFIG_SYS_FSL_USDHC_NUM	2
 #define CONFIG_SYS_FSL_ESDHC_ADDR       0
 
-#define CONFIG_SYS_MMC_IMG_LOAD_PART	1
-
 #endif