Integrate arduino api core

[ramya-subramanyam]

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Arduino Core API symlinked. Now the core API also compiles.
Development Instruction is added.

[jaenrig-ifx]

Good :)
I propose the following improvements here (in a follow up ticket):

--> Add the ArduinoCore-API as a submodule, which will allow us to:

• keep track of the version we are using in the project (from git standpoint).
• use recursive clone to retrieve all the sources

We should put all these things in a folder called "extra" (this name/usage is inspired by this other core https://github.com/arduino/ArduinoCore-renesas/tree/main/extras).

--> Create a .sh script performing all the steps in the development instructions. We might reuse that one for other initial development setups.

[ramya-subramanyam]

Good :) I propose the following improvements here (in a follow up ticket):

--> Add the ArduinoCore-API as a submodule, which will allow us to:

• keep track of the version we are using in the project (from git standpoint).
• use recursive clone to retrieve all the sources

We should put all these things in a folder called "extra" (this name/usage is inspired by this other core https://github.com/arduino/ArduinoCore-renesas/tree/main/extras).

--> Create a .sh script performing all the steps in the development instructions. We might reuse that one for other initial development setups.

I will create a ticket