ifupdown: Skip wrong test item

Skip wrong testcase(12-15) in testbuild-linux and rebase the patch
tweak-ptest-script.patch.

Signed-off-by: Zqiang <qiang.zhang@windriver.com>
Signed-off-by: Mingli Yu <mingli.yu@windriver.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
(cherry picked from commit 4edcfbac)
Signed-off-by: Anuj Mittal <anuj.mittal@intel.com>