diagnostics: fix memory leak in libtextstyle

* src/complain.h, src/complain.c (complain_free): New.
* src/main.c: Use it.

src/complain.c

@@ -278,6 +278,12 @@ complain_init (void)
     }
 }
 
+void
+complain_free (void)
+{
+  caret_free ();
+  styled_ostream_free (errstream);
+}
 
 /* A diagnostic with FLAGS is about to be issued.  With what severity?
    (severity_fatal, severity_error, severity_disabled, or

src/complain.h

@@ -90,6 +90,9 @@ void warnings_argmatch (char *args);
 /** Initialize this module.  */
 void complain_init (void);
 
+/** Reclaim resources.  */
+void complain_free (void);
+
 /** Initialize support for colored messages.  */
 void complain_init_color (void);
 

src/main.c

@@ -234,8 +234,6 @@ main (int argc, char *argv[])
   timevar_stop (tv_total);
   timevar_print (stderr);
 
-  caret_free ();
-
   /* Fix input file now, even if there are errors: that's less
      warnings in the following runs.  */
   if (!fixits_empty ())
@@ -249,5 +247,7 @@ main (int argc, char *argv[])
     }
   uniqstrs_free ();
 
+  complain_free ();
+
   return complaint_status ? EXIT_FAILURE : EXIT_SUCCESS;
 }