armv8: valgrind memleak fixes

Various fixes for memory leaks, adds a target cleanup for aarch64
and ARM CTI objects.

Change-Id: I2267f0894df655fdf73d70c11ed03df0b8f8d07d
Signed-off-by: Matthias Welwarsky <matthias.welwarsky@sysgo.com>
Reviewed-on: http://openocd.zylin.com/4478
Tested-by: jenkins
Reviewed-by: Matthias Welwarsky <matthias@welwarsky.de>
Reviewed-by: Tomas Vanek <vanekt@fbl.cz>

src/openocd.c

@@ -359,6 +359,10 @@ int openocd_main(int argc, char *argv[])
 
 	unregister_all_commands(cmd_ctx, NULL);
 
+	/* free all DAP and CTI objects */
+	dap_cleanup_all();
+	arm_cti_cleanup_all();
+
 	adapter_quit();
 
 	/* Shutdown commandline interface */