core/vm: fix method doc (#20730)

typo in func name in the comment

core/vm/gas.go

@@ -30,7 +30,7 @@ const (
 	GasExtStep     uint64 = 20
 )
 
-// calcGas returns the actual gas cost of the call.
+// callGas returns the actual gas cost of the call.
 //
 // The cost of gas was changed during the homestead price change HF.
 // As part of EIP 150 (TangerineWhistle), the returned gas is gas - base * 63 / 64.