Use canonical env

Workaround bitbake failing to handle /bin/env when it sanity checks for
file runtime dependencies.

Change-Id: Ia967bf28cb3c2de812ad295265e728e0826e80ab
Signed-off-by: Brad Bishop <bradleyb@fuzziesquirrel.com>
diff --git a/tools/sdbus++ b/tools/sdbus++
index 6b0a15c..9f7d111 100755
--- a/tools/sdbus++
+++ b/tools/sdbus++
@@ -1,4 +1,4 @@
-#!/bin/env python
+#!/usr/bin/env python
 import sdbusplus
 import mako.lookup
 import argparse