Improve error message

src/V3Options.cpp

@@ -1160,8 +1160,8 @@ void V3Options::parseOpts(FileLine* fl, int argc, char** argv) VL_MT_DISABLED {
     // Default certain options and error check
     // Detailed error, since this is what we often get when run with minimal arguments
     if (vFiles().empty()) {
-        v3fatal("verilator: No Input Verilog file specified on command line, "
-                "see verilator --help for more information\n");
+        v3fatal("verilator: No input Verilog file specified on command line, "
+                "see 'verilator --help' for more information\n");
     }
 
     // Default prefix to the filename

test_regress/t/t_flag_nofile_bad.out

@@ -1,2 +1,2 @@
-%Error: verilator: No Input Verilog file specified on command line, see verilator --help for more information
+%Error: verilator: No input Verilog file specified on command line, see 'verilator --help' for more information
         ... See the manual at https://verilator.org/verilator_doc.html?v=latest for more assistance.

test_regress/t/t_flag_suggest.out

@@ -20,5 +20,5 @@
         ... See the manual at https://verilator.org/verilator_doc.html?v=latest for more assistance.
 %Error: Unknown language specified: 1364-1997... Suggested alternative: '1364-1995'
         ... See the manual at https://verilator.org/verilator_doc.html?v=latest for more assistance.
-%Error: verilator: No Input Verilog file specified on command line, see verilator --help for more information
+%Error: verilator: No input Verilog file specified on command line, see 'verilator --help' for more information
         ... This fatal error may be caused by the earlier error(s); resolve those first.