piGateway now support for Odroid (C1+)

[acekrystal]

Beside the option -DRASPBERRY added -DODROIDC1 option for the MakeFile.
rdm69.h and .cpp file will take different actions based on these options.
Added ODROIDC1 RST_PIN and defined this as output with pulldown.
Added ODROIDC1 CLK_PIN and defined this as output with pulldown.
Changed ODROIDC1 SPI_CS to pinmode OUTPUT and added pulldown.

In order to work you still need a 2.2K resistor between CLK pin and Gnd.

cleaning Odroid support commit

[abouillot]

I don't have access to an Odroid, so no ways for me to check.
I noticed the makefile in now Odroid by default, which will break most of the users' build. Can you switch it back to Raspberry, or support passing platform as parameters and use Raspberry by default.

[acekrystal]

I agree, I'm really bussy right now, but I will try to make the modifications and push it again. I might also first buy a RBPi and test the script on it to make sure it still works for RBPi users.

I also found a "stack smashing" error in rfm69.ccp when trying to run for multiple day's. I'm kinda new to github, so kinda need to figure out how to prevent my updated pushe doesn't contain other edits yet. Will give it a look some time ;)