asm: remove unused parameter for function Lex (#18058)

core/asm/lexer.go

@@ -95,7 +95,7 @@ type lexer struct {
 
 // lex lexes the program by name with the given source. It returns a
 // channel on which the tokens are delivered.
-func Lex(name string, source []byte, debug bool) <-chan token {
+func Lex(source []byte, debug bool) <-chan token {
 	ch := make(chan token)
 	l := &lexer{
 		input:  string(source),