Creates a bootable disk image from a Rust kernel

USAGE:
    bootimage build [BUILD_OPTS]        Create a bootable disk image

    (for other forms of usage see `bootimage --help`)

BUILD_OPTS:
    --update-bootloader     Update the bootloader dependency.

    Any additional options are directly passed to `cargo build` (see
    `cargo build --help` for possible options). After building, a bootloader
    is downloaded and built, and then combined with the kernel into a bootable
    disk image.

CONFIGURATION:
    The bootloader and the behavior of `bootimage build` can be configured
    through a `[package.metadata.bootimage]` table in the `Cargo.toml`. The
    following options are available to configure the build:

    [package.metadata.bootimage]
    default-target = ""         This target is used if no `--target` is passed
    output = "bootimage.bin"    The output file name
    minimum-image-size = 0      The minimum output file size (in MiB)

    [package.metadata.bootimage.bootloader]
    name = "bootloader"             The bootloader crate name
    version = ""                    The bootloader version that should be used
    git = ""                        Use the bootloader from this git repository
    branch = ""                     The git branch to use (defaults to master)
    path = ""                       Use the bootloader from this local path
    precompiled = false             Whether the bootloader crate is precompiled
    target = "x86_64-bootloader"    Target triple for compiling the bootloader
