package/xvisor: fix build without python interpreter

Fix the following build failures on a system not providing the "python"
interpreter binary raised at least since bump to version 0.3.1 in commit
c4f8b89687 and more probably
since the addition of the package in commit
e23ddf0c13 and
ba904b4066:

/bin/sh: line 1: /home/buildroot/autobuild/instance-2/output-1/build/xvisor-0.3.1/tools/scripts/d2c.py: cannot execute: required file not found

or

/bin/sh: /home/buildroot/instance-0/output-1/build/xvisor-0.3.2/tools/scripts/d2c.py: /usr/bin/python: bad interpreter: No such file or directory

Fixes:
 - http://autobuild.buildroot.org/results/2e100bacc9e9face8351287e4c979c1729709d7b
 - http://autobuild.buildroot.org/results/5d8a08512db1b3095158753e3a7843b0fd6c9749

Signed-off-by: Fabrice Fontaine <fontaine.fabrice@gmail.com>
Signed-off-by: Arnout Vandecappelle <arnout@mind.be>

package/xvisor/0001-TOOLS-d2c-py-explicitly-use-the-python3-interpreter.patch

@@ -0,0 +1,35 @@
+From 888c94e7a121d96aa88f84c58fe7e2bd771fc5ac Mon Sep 17 00:00:00 2001
+From: Julien Olivain <ju.o@free.fr>
+Date: Fri, 25 Aug 2023 21:56:37 +0200
+Subject: [PATCH] TOOLS: d2c.py: explicitly use the python3 interpreter
+
+When compiling Xvisor on a system not providing the "python"
+interpreter binary, compilation fails with output:
+
+    (d2c)       core/vio/keymaps/modifiers.c
+    /bin/sh: 1: /build/xvisor-0.3.2/tools/scripts/d2c.py: not found
+
+This commit fixes the issue following the PEP 394 recommendation:
+https://peps.python.org/pep-0394/
+
+It sets the "shebang" to `#! /usr/bin/env python3` to allow using other
+interpreters in the PATH, or virtual environment.
+
+Signed-off-by: Julien Olivain <ju.o@free.fr>
+
+Upstream: https://github.com/xvisor/xvisor/commit/888c94e7a121d96aa88f84c58fe7e2bd771fc5ac
+Signed-off-by: Fabrice Fontaine <fontaine.fabrice@gmail.com>
+---
+ tools/scripts/d2c.py | 2 +-
+ 1 file changed, 1 insertion(+), 1 deletion(-)
+
+diff --git a/tools/scripts/d2c.py b/tools/scripts/d2c.py
+index b46a7bc468..daac4a5450 100755
+--- a/tools/scripts/d2c.py
++++ b/tools/scripts/d2c.py
+@@ -1,4 +1,4 @@
+-#!/usr/bin/python
++#! /usr/bin/env python3
+ #/**
+ # Copyright (c) 2013 Anup Patel.
+ # All rights reserved.

package/xvisor/xvisor.mk

@@ -11,7 +11,7 @@ XVISOR_LICENSE = GPL-2.0+
 XVISOR_LICENSE_FILES = COPYING
 XVISOR_INSTALL_IMAGES = YES
 XVISOR_INSTALL_TARGET = NO
-XVISOR_DEPENDENCIES = host-bison host-dtc host-flex
+XVISOR_DEPENDENCIES = host-bison host-dtc host-flex host-python3
 
 XVISOR_MAKE_TARGETS = all