ethereum: add Akroma chain (#387)

firmware/ethereum.c

@@ -263,6 +263,7 @@ static void ethereumFormatAmount(const bignum256 *amnt, const TokenType *token,
 				case  820: suffix = " CLO";  break;  // Callisto
 				case 1987: suffix = " EGEM"; break;  // EtherGem
 				case 31102: suffix = " ESN"; break;  // Ethersocial Network
+				case 200625: suffix = " AKA"; break; // Akroma
 				default  : suffix = " UNKN"; break;  // unknown chain
 			}
 		}