* Adds new cpu architectures propeller1 and propeller2.

These cpu architectures allow targeting the Parallax Propeller 1 and Propeller 2, which are both very special microcontrollers with 512 registers and 8 cpu cores.

Resolves #21559

* Adds std.elf.EM.PROPELLER and std.elf.EM.PROPELLER2
* Fixes missing switch prongs in src/codegen/llvm.zig
* Fixes order in std.Target.Arch

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Co-authored-by: Felix "xq" Queißner <git@random-projects.net>