Document removal of 'register' from flex/bison output

In each .l and .y input file that has instructions for manual
transformation of the output to include a step to remove the 'register'
storage specifier.

Source/cmCommandArgumentLexer.in.l

@@ -22,6 +22,7 @@ Modify cmCommandArgumentLexer.cxx:
   - add #include "cmStandardIncludes.h" to top of file
   - put header block at top of file
   - remove TABs
+  - remove use of the 'register' storage class specifier
   - remove "yyscanner" argument from these methods:
       yy_fatal_error, cmCommandArgument_yyalloc, cmCommandArgument_yyrealloc, cmCommandArgument_yyfree
   - remove all YY_BREAK lines occurring right after return statements

Source/cmCommandArgumentParser.y

@@ -20,6 +20,7 @@ Run bison like this:
 
 Modify cmCommandArgumentParser.cxx:
   - remove TABs
+  - remove use of the 'register' storage class specifier
   - put header block at top of file
 
 */

Source/cmDependsFortranLexer.in.l

@@ -30,6 +30,7 @@ Run flex like this:
 
 Modify cmDependsFortranLexer.cxx:
   - remove TABs
+  - remove use of the 'register' storage class specifier
   - remove "yyscanner" argument from these methods:
       yy_fatal_error, cmDependsFortran_yyalloc, cmDependsFortran_yyrealloc, cmDependsFortran_yyfree
   - remove "yyscanner = NULL" from end of cmDependsFortran_yylex_destroy

Source/cmDependsFortranParser.y

@@ -33,6 +33,7 @@ Run bison like this:
 
 Modify cmDependsFortranParser.cxx:
   - remove TABs
+  - remove use of the 'register' storage class specifier
   - Remove the yyerrorlab block in range ["goto yyerrlab1", "yyerrlab1:"]
 */
 

Source/cmDependsJavaLexer.in.l

@@ -20,6 +20,7 @@ Run flex like this:
 
 Modify cmDependsJavaLexer.c:
   - remove TABs
+  - remove use of the 'register' storage class specifier
   - remove "yyscanner" argument from these methods:
       yy_fatal_error, cmDependsJava_yyalloc, cmDependsJava_yyrealloc, cmDependsJava_yyfree
   - remove all YY_BREAK lines occurring right after return statements

Source/cmDependsJavaParser.y

@@ -20,6 +20,7 @@ Run bison like this:
 
 Modify cmDependsJavaParser.cxx:
   - remove TABs
+  - remove use of the 'register' storage class specifier
   - add __HP_aCC to the #if test for yyerrorlab warning suppression
 
 */

Source/cmExprLexer.in.l

@@ -20,6 +20,7 @@ Run flex like this:
 
 Modify cmExprLexer.cxx:
   - remove TABs
+  - remove use of the 'register' storage class specifier
   - remove "yyscanner" argument from these methods:
       yy_fatal_error, cmExpr_yyalloc, cmExpr_yyrealloc, cmExpr_yyfree
   - remove all YY_BREAK lines occurring right after return statements

Source/cmExprParser.y

@@ -20,6 +20,7 @@ Run bison like this:
 
 Modify cmExprParser.cxx:
   - remove TABs
+  - remove use of the 'register' storage class specifier
   - add __HP_aCC to the #if test for yyerrorlab warning suppression
 
 */

Source/cmListFileLexer.in.l

@@ -20,6 +20,7 @@ Run flex like this:
 
 Modify cmListFileLexer.c:
   - remove TABs
+  - remove use of the 'register' storage class specifier
   - remove the yyunput function
   - add a statement "(void)yyscanner;" to the top of these methods:
       yy_fatal_error, cmListFileLexer_yyalloc, cmListFileLexer_yyrealloc, cmListFileLexer_yyfree