build: make sure we are calling python3 in all scripts

Jira: ZEP-1759
Change-Id: I0fc7329f806ca0049c555d3402dd145e92e54028
Signed-off-by: Anas Nashif <anas.nashif@intel.com>
diff --git a/scripts/qemu-machine-hack.py b/scripts/qemu-machine-hack.py
old mode 100644
new mode 100755
index 1412ed8..3acd50c
--- a/scripts/qemu-machine-hack.py
+++ b/scripts/qemu-machine-hack.py
@@ -1,3 +1,5 @@
+#!/usr/bin/env python3
+
 import sys
 
 # For some baffling reason IAMCU sets the instruction set architecture