snowball does not boot due to wrong partition during untangling of boot commands

Since the partition number for snowball devices are not re-written properly with latest changes of untangling boot commands, these devices do not boot. As per the latest conf, snowball's boot commands look like the following:

<snip>
boot_cmds = mmc rescan 1,
    setenv bootcmd "'fatload mmc 1:3 0x00100000 /uImage;
    bootm 0x00100000'",
    setenv bootargs "'console=ttyAMA2,115200n8 ip=dhcp vmalloc=300M
    root=/dev/mmcblk1p5 rootwait mem=128M@0 mali.mali_mem=32M@128M
    hwmem=168M@160M mem=48M@328M mem_issw=1M@383M mem=640M@384M'",
    boot
</snip>