scripts/qemu-gdb: Use Python 3 interpreter

Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: John Snow <jsnow@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20200512103238.7078-3-philmd@redhat.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>

scripts/qemu-gdb.py

@@ -1,5 +1,5 @@
-#!/usr/bin/python
-
+#!/usr/bin/env python3
+#
 # GDB debugging support
 #
 # Copyright 2012 Red Hat, Inc. and/or its affiliates