radio_mac.c: Removed the line that sets CHANNR.  We want to let the be done by higher-level code.  Also removed some old TODOs.
radio_mac.c: Removed the line that sets CHANNR.  We want to let the be done by higher-level code.  Also removed some old TODOs.

novagannas/wixel-xDrip,novagannas/wixel-xDrip,sm6xmm/wixel-xDrip,attackcrow/wixel,StephenBlackWasAlreadyTaken/wixel-xDrip,raduiliescu/wixel-DexDrip,markncooper/burnerlight,raduiliescu/wixel-DexDrip,jamorham/wixel-xDrip,Cagier/wixel-xDrip,markncooper/burnerlight,Cagier/wixel-xDrip,pdg137/wixel-sdk,novagannas/wixel-xDrip,pdg137/wixel-sdk,pdg137/wixel-sdk,raduiliescu/wixel-DexDrip,jamorham/wixel-xDrip,kevinwchang/wixel-sdk,saercnap/wixel-DexDrip,StephenBlackWasAlreadyTaken/wixel-xDrip,attackcrow/wixel,jamorham/wixel-xDrip,saercnap/wixel-DexDrip,Cagier/wixel-xDrip,sm6xmm/wixel-xDrip,sm6xmm/wixel-xDrip,saercnap/wixel-DexDrip,attackcrow/wixel,kevinwchang/wixel-sdk,attackcrow/wixel,jamorham/wixel-xDrip,StephenBlackWasAlreadyTaken/wixel-xDrip,markncooper/burnerlight,kevinwchang/wixel-sdk,sm6xmm/wixel-xDrip