Add MathChain SS58 address type (#7158)

Author: rayshitou

ss58-registry.json

@@ -244,6 +244,24 @@
 			"standardAccount": "*25519",
 			"website": "https://centrifuge.io/"
 		},
+		{
+			"prefix": 39,
+			"network": "mathchain",
+			"displayName": "MathChain mainnet",
+			"symbols": ["MATH"],
+			"decimals": [18],
+			"standardAccount": "*25519",
+			"website": "https://mathwallet.org"
+		},
+		{
+			"prefix": 40,
+			"network": "mathchain-testnet",
+			"displayName": "MathChain testnet",
+			"symbols": ["MATH"],
+			"decimals": [18],
+			"standardAccount": "*25519",
+			"website": "https://mathwallet.org"
+		},
 		{
 			"prefix": 42,
 			"network": "substrate",