Fix some syntax error context by splitting internal parse and lex filelines

src/V3ParseLex.cpp

@@ -52,7 +52,7 @@ void V3ParseImp::lexUnputString(const char* textp, size_t length) {
 
 int V3ParseImp::yylexReadTok() {
     // Call yylex() remembering last non-whitespace token
-    parsep()->fileline()->startToken();
+    parsep()->lexFileline()->startToken();
     int token = parsep()->m_lexerp->yylex();
     m_lexPrevToken = token;  // Save so can find '#' to parse following number
     return token;