util: Use /usr/bin/env as wrapper to look up python

This way users are not constrained to have it installed as
/usr/bin/python.

Change-Id: I822b6c402004aad8f2353e71afbd8ee3f9d26d45
Signed-off-by: Nico Huber <nico.h@gmx.de>
Reviewed-on: https://review.coreboot.org/13285
Tested-by: build bot (Jenkins)
Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net>
Reviewed-by: Patrick Georgi <pgeorgi@google.com>
4 files changed