Add IOT2050 board into mraa Intel nodes

[fr0st61te]

Porting from IOT2050 to mraa Intel nodes:

1. add IOT2050 board into PWM, AIN, DOUT
2. clean up on close for PWM, AIN, DOUT
3. add LED into GPIO category

[linux-foundation-easycla[bot]]

The committers listed above are authorized under a signed CLA.

• :white_check_mark: login: fr0st61te / name: Ivan Mikhaylov (d1bd7347ab8b865797eb51139163082db062721e, 92cabd3b65969ac42091a5c43c076c4a8473433c, 91a3d2b8abdfc97af602f61dabf2650252407cad, 7050f0a1479428d182cf80368e8763579c3defc0, 24079943b356ed2691515d460179b1d322a29410)
• :white_check_mark: login: jan-kiszka / name: Jan Kiszka (1f30bdd154445395fb6985d41d9c7f2fbfcd933f)

[Steve-Mcl]

@fr0st61te thanks for this. Did you sign the EasyCLA mentioned above ↑ ?

[jan-kiszka]

We likely need to run this through our corporate process first, clarifying ATM.

[dceejay]

Any joy with your signoff process ?

[fr0st61te]

Any joy with your signoff process ?

Now, it's done :)

[dceejay]

Many thanks ! Published as v0.2.0