Removing exit calls from config parser

* config.h: cleanup, left only internally needed definitions
* config.c: removed exit calls, use yyerror and yywarning
* config_gram.y: (Dito.)
* lexer.l: (Dito.)
* libavrdude.h: removed internal definitions of config parser
* main.c: removed yyerror, it is now in config.c
* jtagmkII.c: added missing free in error case
* pgm.c: replaced exits by returns
* pickit2.c: add missing return



git-svn-id: svn://svn.savannah.nongnu.org/avrdude/trunk/avrdude@1322 81a1dc3b-b13d-400b-aceb-764788c761c2

pickit2.c

@@ -1318,6 +1318,8 @@ static int pickit2_nousb_open (struct programmer_t *pgm, char * name) {
             "%s: error: no usb support. Please compile again with libusb installed.\n",
 #endif
             progname);
+
+    return -1;
 }
 
 void pickit2_initpgm (PROGRAMMER * pgm)