Increase the error verbosity of the Verilog parser

Bison is instructed to generate verbose error messages for the Verilog parser.

This results in more helpful syntax error messages at least in some cases.

regression/smv/syntax-errors/syntax1.desc

@@ -0,0 +1,7 @@
+CORE
+syntax1.smv
+
+^file .* line 3: syntax error, unexpected VAR, expecting string or "'" before 'VAR'$
+^EXIT=1$
+^SIGNAL=0$
+--

regression/smv/syntax-errors/syntax1.smv

@@ -0,0 +1,4 @@
+MODULE -- forgot the name
+
+VAR abc : BOOLEAN;
+

regression/smv/syntax-errors/syntax2.desc

@@ -0,0 +1,7 @@
+CORE
+syntax2.smv
+
+^file .* line 3: syntax error, unexpected VAR before 'VAR'$
+^EXIT=1$
+^SIGNAL=0$
+--

regression/smv/syntax-errors/syntax2.smv

@@ -0,0 +1,4 @@
+-- forgot the MODULE
+
+VAR abc : BOOLEAN;
+

regression/smv/syntax-errors/syntax3.desc

@@ -0,0 +1,7 @@
+CORE
+syntax3.smv
+
+^file .* line 3: syntax error, unexpected string, expecting number before 'not_a_number'$
+^EXIT=1$
+^SIGNAL=0$
+--

regression/smv/syntax-errors/syntax3.smv

@@ -0,0 +1,4 @@
+MODULE main
+
+VAR foobar : 1.. not_a_number;
+

regression/verilog/preprocessor/ifdef1.desc

@@ -1,7 +1,7 @@
 CORE
 ifdef1.v
 
-^file ifdef1\.v line 4: syntax error before 'syntax'$
+^file ifdef1\.v line 4: syntax error, unexpected .* before 'syntax'$
 ^EXIT=1$
 ^SIGNAL=0$
 --

regression/verilog/preprocessor/ifdef2.desc

@@ -1,7 +1,7 @@
 CORE
 ifdef2.v
 
-^file ifdef2\.v line 4: syntax error before 'syntax'$
+^file ifdef2\.v line 4: syntax error, unexpected .* before 'syntax'$
 ^EXIT=1$
 ^SIGNAL=0$
 --

regression/verilog/preprocessor/multi-line-define2.desc

@@ -1,7 +1,7 @@
 CORE
 multi-line-define2.v
 
-^file multi-line-define2\.v line 4: syntax error before 'syntax'$
+^file multi-line-define2\.v line 4: syntax error, unexpected .* before 'syntax'$
 ^EXIT=1$
 ^SIGNAL=0$
 --

regression/verilog/preprocessor/multi-line-define3.desc

@@ -1,7 +1,7 @@
 CORE
 multi-line-define3.v
 
-^file multi-line-define3\.v line 4: syntax error before 'syntax'$
+^file multi-line-define3\.v line 4: syntax error, unexpected .* before 'syntax'$
 ^EXIT=1$
 ^SIGNAL=0$
 --

regression/verilog/syntax-errors/syntax1.desc

@@ -0,0 +1,7 @@
+CORE
+syntax1.sv
+
+^file .* line 1: syntax error, unexpected ';', expecting TOK_NON_TYPE_IDENTIFIER before ';'$
+^EXIT=1$
+^SIGNAL=0$
+--

regression/verilog/syntax-errors/syntax1.sv

@@ -0,0 +1 @@
+module ;// forgot the name

regression/verilog/syntax-errors/syntax2.desc

@@ -0,0 +1,7 @@
+CORE
+syntax2.sv
+
+^file syntax2.sv line 3: syntax error, unexpected byte, expecting ';' before 'byte'$
+^EXIT=1$
+^SIGNAL=0$
+--

regression/verilog/syntax-errors/syntax2.sv

@@ -0,0 +1,6 @@
+module main // forgot the ;
+
+byte some_var;
+
+endmodule
+

regression/verilog/syntax-errors/syntax3.desc

@@ -0,0 +1,7 @@
+CORE
+syntax3.sv
+
+^file syntax3.sv line 1: syntax error, unexpected ';' before ';'$
+^EXIT=1$
+^SIGNAL=0$
+--

regression/verilog/syntax-errors/syntax3.sv

@@ -0,0 +1 @@
+module main(; // forgot the )

src/smvlang/parser.y

@@ -1,3 +1,4 @@
+/* increase verbosity of error messages, to include expected tokens */
 %define parse.error verbose
 
 %{

src/verilog/parser.y

@@ -1,3 +1,6 @@
+/* increase verbosity of error messages, to include expected tokens */
+%define parse.error verbose
+
 %{
 /*******************************************************************\