jtag/core, target: unregister JTAG events

Also call adapter_exit() before command_exit() as the latter releases
Jim interpreter so JTAG events should be released before.

Fixes memory leak reported by valgrind

Change-Id: I493f3fcba34ea2b4234148e79a4e329c866e0f05
Signed-off-by: Tomas Vanek <vanekt@fbl.cz>
Reviewed-on: http://openocd.zylin.com/4474
Tested-by: jenkins
Reviewed-by: Matthias Welwarsky <matthias@welwarsky.de>

src/openocd.c

@@ -359,11 +359,11 @@ int openocd_main(int argc, char *argv[])
 
 	unregister_all_commands(cmd_ctx, NULL);
 
+	adapter_quit();
+
 	/* Shutdown commandline interface */
 	command_exit(cmd_ctx);
 
-	adapter_quit();
-
 	free_config();
 
 	if (ERROR_FAIL == ret)