Keep only Regexp.* reference

The actual reference is defined in Regexp_pcre or in Regexp_str
but the correct definition is included in the Regexp module that
./configure generates.

coccinelle.ml

@@ -1,5 +1,7 @@
 (* entry point when calling Coccinelle from OCaml code *)
 
+open Coccinelle_modules
+
 let __init_debugger = !Common.debugger
 let __init_profile = !Common.profile
 let __init_show_trace_profile = !Common.show_trace_profile
@@ -92,10 +94,7 @@ let __init_initialization_stack = !Iteration.initialization_stack
 let __init_base_file_list = !Iteration.base_file_list
 let __init_parsed_virtual_rules = !Iteration.parsed_virtual_rules
 let __init_parsed_virtual_identifiers = !Iteration.parsed_virtual_identifiers
-(* not sure what todo with the following - config dependent *)
-(*let __init_pcre_support1 = !Regexp.pcre_support
-let __init_pcre_support2 = !Regexp_pcre.pcre_support
-let __init_pcre_support3 = !Regexp_str.pcre_support*)
+let __init_pcre_support1 = !Regexp.pcre_support
 let __init_path = !Flag_parsing_c.path
 let __init_std_h = !Flag_parsing_c.std_h
 let __init_common_h = !Flag_parsing_c.common_h
@@ -404,10 +403,7 @@ let coccinelle arglist =
   Iteration.base_file_list := __init_base_file_list;
   Iteration.parsed_virtual_rules := __init_parsed_virtual_rules;
   Iteration.parsed_virtual_identifiers := __init_parsed_virtual_identifiers;
-(* not sure what todo with the following - config dependent *)
-(*  Regexp.pcre_support := __init_pcre_support1;
-  Regexp_pcre.pcre_support := __init_pcre_support2;
-  Regexp_str.pcre_support := __init_pcre_support3;*)
+  Regexp.pcre_support := __init_pcre_support1;
   Flag_parsing_c.path := __init_path;
   Flag_parsing_c.std_h := __init_std_h;
   Flag_parsing_c.common_h := __init_common_h;