AOT Support for RH850G3M's Proprietary ISA

[kiranbaliga91]

Is your feature request related to a problem? Please describe.
I am trying to execute AOT on a RH850G3M based microcontroller. Unfortunately, RH850G3M's Proprietary ISA is not supported by wamrc compiler.

Describe the solution you'd like
wamrc compiler and WAMR must support AOT for RH850G3M CPU Instruction.

Describe alternatives you've considered
WAMR Interpreter mode is working on RH850G3M microcontroller

Additional context
Is it possible that we link a 3rd party compiler with wamrc to convert .wasm into RH850G3M specific CPU instruction set .aot file?

[TianlongLiang]

same as #4706, let's discuss there