This ensure a reliable built without host contamination, this
will also disable the usage of ghostscript.
[YOCTO #2966]
(From OE-Core rev: 90bccaa290d2bc04c7ea1bbeb2cddb3509d0d380)
Signed-off-by: Saul Wold <sgw@linux.intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>