Support mips

[ojeda]

MIPS little-endian, both 32-bit and 64-bit, is supported by Debian, which means we should eventually support the mipsel and mips64el architectures.

Linux mips targets with official Ubuntu binutils etc. support:

Linux arch  QEMU target       LLVM target  Ubuntu binutils                   Example Rust triple
----------  ----------------  -----------  --------------------------------  -------------------------------

mips        mips-softmmu      Mips         binutils-mips-linux-gnu           mips-unknown-linux-gnu
mips        mipsel-softmmu    Mips         binutils-mipsel-linux-gnu         mipsel-unknown-linux-gnu
mips        mips64-softmmu    Mips         binutils-mips64-linux-gnuabi64    mips64-unknown-linux-gnuabi64
mips        mips64el-softmmu  Mips         binutils-mips64el-linux-gnuabi64  mips64el-unknown-linux-gnuabi64

[FlyGoat]

Related discussion: rust-embedded/wg#792 (comment)

[FlyGoat]

Initial Patch: https://lore.kernel.org/linux-mips/20240903-mips-rust-v1-0-0fdf0b2fd58f@flygoat.com/