env: Rename SYS_MMC_ENV_DEV to ENV_MMC_DEVICE_INDEX

Rename the variable and add ENV_ prefix, so that all configuration
options which are related to environment would have an CONFIG_ENV_
prefix. No functional change.

Use ENV_MMC_DEVICE_INDEX to clarify this is the SD/MMC device
index, a number, as enumerated by U-Boot. Update the help text
accordingly.

Signed-off-by: Marek Vasut <marek.vasut+renesas@mailbox.org>
diff --git a/drivers/mmc/mmc.c b/drivers/mmc/mmc.c
index 9421a84..2c1f4f9 100644
--- a/drivers/mmc/mmc.c
+++ b/drivers/mmc/mmc.c
@@ -3278,8 +3278,8 @@
 
 __weak int mmc_get_env_dev(void)
 {
-#ifdef CONFIG_SYS_MMC_ENV_DEV
-	return CONFIG_SYS_MMC_ENV_DEV;
+#ifdef CONFIG_ENV_MMC_DEVICE_INDEX
+	return CONFIG_ENV_MMC_DEVICE_INDEX;
 #else
 	return 0;
 #endif
diff --git a/drivers/net/fm/fm.c b/drivers/net/fm/fm.c
index a8caa0f..146f3f1 100644
--- a/drivers/net/fm/fm.c
+++ b/drivers/net/fm/fm.c
@@ -410,12 +410,12 @@
 			spi_flash_free(ucode_flash);
 		}
 	} else if (src == BOOT_SOURCE_SD_MMC) {
-		int dev = CONFIG_SYS_MMC_ENV_DEV;
+		int dev = CONFIG_ENV_MMC_DEVICE_INDEX;
 
 		addr = malloc(CONFIG_SYS_QE_FMAN_FW_LENGTH);
 		u32 cnt = CONFIG_SYS_QE_FMAN_FW_LENGTH / 512;
 		u32 blk = CONFIG_SYS_FMAN_FW_ADDR / 512;
-		struct mmc *mmc = find_mmc_device(CONFIG_SYS_MMC_ENV_DEV);
+		struct mmc *mmc = find_mmc_device(CONFIG_ENV_MMC_DEVICE_INDEX);
 
 		if (!mmc) {
 			printf("\nMMC cannot find device for ucode\n");
@@ -514,11 +514,11 @@
 		spi_flash_free(ucode_flash);
 	}
 #elif defined(CONFIG_SYS_QE_FMAN_FW_IN_MMC)
-	int dev = CONFIG_SYS_MMC_ENV_DEV;
+	int dev = CONFIG_ENV_MMC_DEVICE_INDEX;
 	void *addr = malloc(CONFIG_SYS_QE_FMAN_FW_LENGTH);
 	u32 cnt = CONFIG_SYS_QE_FMAN_FW_LENGTH / 512;
 	u32 blk = CONFIG_SYS_FMAN_FW_ADDR / 512;
-	struct mmc *mmc = find_mmc_device(CONFIG_SYS_MMC_ENV_DEV);
+	struct mmc *mmc = find_mmc_device(CONFIG_ENV_MMC_DEVICE_INDEX);
 
 	if (!mmc)
 		printf("\nMMC cannot find device for ucode\n");
diff --git a/drivers/net/phy/cortina.c b/drivers/net/phy/cortina.c
index d043e85..be480ec 100644
--- a/drivers/net/phy/cortina.c
+++ b/drivers/net/phy/cortina.c
@@ -170,10 +170,10 @@
 			spi_flash_free(ucode_flash);
 		}
 	} else if (src == BOOT_SOURCE_SD_MMC) {
-		int dev = CONFIG_SYS_MMC_ENV_DEV;
+		int dev = CONFIG_ENV_MMC_DEVICE_INDEX;
 		u32 cnt = CONFIG_CORTINA_FW_LENGTH / 512;
 		u32 blk = cortina_fw_addr / 512;
-		struct mmc *mmc = find_mmc_device(CONFIG_SYS_MMC_ENV_DEV);
+		struct mmc *mmc = find_mmc_device(CONFIG_ENV_MMC_DEVICE_INDEX);
 
 		if (!mmc) {
 			puts("Failed to find MMC device for Cortina ucode\n");
@@ -223,10 +223,10 @@
 		spi_flash_free(ucode_flash);
 	}
 #elif defined(CONFIG_SYS_CORTINA_FW_IN_MMC)
-	int dev = CONFIG_SYS_MMC_ENV_DEV;
+	int dev = CONFIG_ENV_MMC_DEVICE_INDEX;
 	u32 cnt = CONFIG_CORTINA_FW_LENGTH / 512;
 	u32 blk = cortina_fw_addr / 512;
-	struct mmc *mmc = find_mmc_device(CONFIG_SYS_MMC_ENV_DEV);
+	struct mmc *mmc = find_mmc_device(CONFIG_ENV_MMC_DEVICE_INDEX);
 
 	if (!mmc) {
 		puts("Failed to find MMC device for Cortina ucode\n");
diff --git a/drivers/qe/qe.c b/drivers/qe/qe.c
index 9631337..69b7de0 100644
--- a/drivers/qe/qe.c
+++ b/drivers/qe/qe.c
@@ -243,7 +243,7 @@
 				CFG_SYS_FSL_QSPI_BASE);
 
 	if (src == BOOT_SOURCE_SD_MMC) {
-		int dev = CONFIG_SYS_MMC_ENV_DEV;
+		int dev = CONFIG_ENV_MMC_DEVICE_INDEX;
 		u32 cnt = CONFIG_SYS_QE_FMAN_FW_LENGTH / 512;
 		u32 blk = CONFIG_SYS_QE_FW_ADDR / 512;
 
@@ -252,7 +252,7 @@
 			return;
 		}
 		addr = malloc(CONFIG_SYS_QE_FMAN_FW_LENGTH);
-		struct mmc *mmc = find_mmc_device(CONFIG_SYS_MMC_ENV_DEV);
+		struct mmc *mmc = find_mmc_device(CONFIG_ENV_MMC_DEVICE_INDEX);
 
 		if (!mmc) {
 			free(addr);
@@ -277,7 +277,7 @@
 
 	void *addr = (void *)CONFIG_SYS_QE_FW_ADDR;
 #ifdef CONFIG_SYS_QE_FMAN_FW_IN_MMC
-	int dev = CONFIG_SYS_MMC_ENV_DEV;
+	int dev = CONFIG_ENV_MMC_DEVICE_INDEX;
 	u32 cnt = CONFIG_SYS_QE_FMAN_FW_LENGTH / 512;
 	u32 blk = CONFIG_SYS_QE_FW_ADDR / 512;
 
@@ -286,7 +286,7 @@
 		return;
 	}
 	addr = malloc(CONFIG_SYS_QE_FMAN_FW_LENGTH);
-	struct mmc *mmc = find_mmc_device(CONFIG_SYS_MMC_ENV_DEV);
+	struct mmc *mmc = find_mmc_device(CONFIG_ENV_MMC_DEVICE_INDEX);
 
 	if (!mmc) {
 		printf("\nMMC cannot find device for ucode\n");