gitignore: remove client tests paths

Client tests are now in separate repo

Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org>
client/kernel.py: fix various mistypes

- Pass make_opt argument during modules compilation as we do
  during vmlinux compilation
- fix mistype in apply_overrides()

Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org>
client/kernel_unittest.py: add empty value for make_opts

Signed-off-by: Cleber Rosa <crosa@redhat.com>