Include field descriptions for picotool otp list

[kilograham]

$ picotool otp list crit1.boot_arch
ROW 0x0040: OTP_DATA_CRIT1
        "Page 1 critical boot flags (RBIT-8)"
    field BOOT_ARCH (bit 3)

vs

$ picotool otp get crit1.boot_arch
ROW 0x0040: OTP_DATA_CRIT1
        "Page 1 critical boot flags (RBIT-8)"

    VALUE 0x000000

    field BOOT_ARCH (bit 3) = 0
        "Set the default boot architecture, 0=ARM 1=RISC-V. Ignored if ARM_DISABLE, RISCV_DISABLE or SECURE_BOOT_ENABLE is set."

There is a -n for not showing descriptions; perhaps the default should be to show field descriptions if you are matching on field, and maybe add another option to force showing field descriptions always