bug #34302: Feature request : device configuration with parent classes

* config_gram.y: if memory section is overwritten old entry is removed
        
(not in original patch)
* config_gram.y: if programmer or part is defined twice, a warning is
  output and the first instance is removed
        
General cleanup and free functions, so valgrind does not report any lost
blocks at program end.
* avrpart.[hc]: added avr_free_(opcode|mem|part) functions
* pgm.[hc]: added pgm_free function
* update.[hc]: added free_update functions
* config.[hc]: added cleanup_config function, use yylex_destroy to reset
  the lexer after usage. (So it can be reused.)
* main.c: add cleanup_main function which is called by atexit() (This 
  frees all lists so that at program exit only really lost memory is 
  reported by valgrind.)
* usbasp.c: added libusb_free_device_list() and libusb_exit() calls to
  avoid lost memory
* buspirate.c: moved memory allocation from initpgm to setup and added 
  free in teardown
* configure.ac: add definition of HAVE_YYLEX_DESTROY if $LEX is flex.
* Makefile.am: added . in front of SUBDIRS to build avrdude before trying
  to use it for creating the part list for the docs.



git-svn-id: svn://svn.savannah.nongnu.org/avrdude/trunk/avrdude@1041 81a1dc3b-b13d-400b-aceb-764788c761c2

pgm.c

@@ -135,6 +135,17 @@ PROGRAMMER * pgm_new(void)
   return pgm;
 }
 
+void pgm_free(PROGRAMMER * const p)
+{
+  ldestroy_cb(p->id,free);
+  p->id = NULL;
+  /* this is done by pgm_teardown, but usually cookie is not set to NULL */
+  /* if (p->cookie !=NULL) {
+    free(p->cookie);
+    p->cookie = NULL;
+  }*/
+  free(p);
+}
 
 static void pgm_default(void)
 {