这个vold.fstab文件怎么改?
## Example of a standard sdcard mount for the emulator / Dream
# Mounts the first usable partition of the specified device
dev_mount sdcard /mnt/sdcard2 emmc@fat /devices/platform/goldfish_mmc.0 /devices/platform/mtk-sd.0/mmc_host
dev_mount sdcard /mnt/sdcard auto /devices/platform/goldfish_mmc.1 /devices/platform/mtk-sd.1/mmc_host
## Example of a dual card setup
# dev_mount left_sdcard /mnt/sdcard1 auto /devices/platform/goldfish_mmc.0 /devices/platform/mtk-sd.0/mmc_host/mmc0
# dev_mount right_sdcard /mnt/sdcard2 auto /devices/platform/goldfish_mmc.1 /devices/platform/mtk-sd.2/mmc_host/mmc2
## Example of specifying a specific partition for mounts
# dev_mount sdcard /mnt/sdcard 2 /devices/platform/goldfish_mmc.0 /devices/platform/msm_sdcc.2/mmc_host/mmc1
## Example of a standard sdcard mount for the emulator / Dream
# Mounts the first usable partition of the specified device
dev_mount sdcard /mnt/sdcard2 emmc@fat /devices/platform/goldfish_mmc.0 /devices/platform/mtk-sd.0/mmc_host
dev_mount sdcard /mnt/sdcard auto /devices/platform/goldfish_mmc.1 /devices/platform/mtk-sd.1/mmc_host
## Example of a dual card setup
# dev_mount left_sdcard /mnt/sdcard1 auto /devices/platform/goldfish_mmc.0 /devices/platform/mtk-sd.0/mmc_host/mmc0
# dev_mount right_sdcard /mnt/sdcard2 auto /devices/platform/goldfish_mmc.1 /devices/platform/mtk-sd.2/mmc_host/mmc2
## Example of specifying a specific partition for mounts
# dev_mount sdcard /mnt/sdcard 2 /devices/platform/goldfish_mmc.0 /devices/platform/msm_sdcc.2/mmc_host/mmc1