[Embedded] Add ARMv5TE to list of recognized architectures (#90023)
Adds support for Swift Embedded ARMv5TE target (e.g. Nintendo DS). This
adds ARMv5TE as a recognized embedded architecture and builds a stdlib
module for it.
Since LLVM natively supports ARMv5TE, this is all that's needed to write
Swift for the Nintendo DS. Right now this is needed for
[swift-embedded-nds](https://github.com/MillerTechnologyPeru/swift-embedded-nds),
which is currently just compiling for Armv4 since its backwards
compatible.